Rounds the value of a double to the nearest whole number.
Arrays that store arrays. The methods associated with these are the same as regular arrays.
A 2D Array is an array of arrays, used to represent tables, grids, and matrices.
A 2d list is a list whose items are also lists.
Allows putting links on a web page. It uses the href attribute to specify what the link should point to.
Allows adding an image to a web page. It is self-closing. The attributes of a image tags include src, which specifies where to get the image from (the url for an image ), and width and height attributes, which specify the size of the image in pixels.
defines a list item inside an HMTL list.
Defines an unordered list in HTML.
Java key term used to denote the user intendeds to override a method.
AAA in network security stands for Authentication, Authorization and Accounting. It is used to refer to a family of protocols which mediate network access.
A class, usually at the top of a Class Hierarchy, that cannot be instantiated, because not all of its methods are defined.
An art movement in the 1940s and 1950s characterized by creative spontaneous acts, such as Jackson Pollock's dripping paintings.
A method, written in an Abstract Class, that is not defined. The word `abstract` must come right before the method's return type. It is up to the subclass to fill in the definition for the abstract method.
Managing complexity by "abstracting away" information and detail, in order to focus on the relevant concepts.
In network security, access control is the restriction of access to a place or other resource on a network. Permission to access a resource is called authorization.
In network security, access control is the restriction of access to a place or other resource on a network. Permission to access a resource is called authorization.
Determines who has access to using the method when writing classes and objects.
A method that enables user to obtain information about an object’s instance and static variables.
Methods used to access instance variable and object data. Also referred to as getter methods.
Association for Computing Machinery: organization for computing professionals to provide guidance related to ethics and responsibilities.
A triangle where all angles are less than 90 degrees.
An algorithm is a set of steps or rules to follow to solve a particular problem.
Step-by-step process that solves a problem.
A variable that references an existing object. When the alias variable is manipulated, so is the original object, and vice versa.
Two object references are considered aliases when they both reference the same object.
Two object references are considered aliases when they both reference the same object.
Logical operator that ANDs two boolean values. Written as `&&`. `a && b` will be true if both `a` and `b` are true.
Logical operator that ANDs two boolean values. Written as `&&`. `a && b` will be true if both `a` and `b` are true.
Showing several still images one after another very quickly, to give the illusion of animated movement.
Creating the illusion of motion using rapidly changing still images.
Add a particular item to the end of a list.
APIs and libraries simplify complex programming tasks by providing sets of clearly defined methods of communication among various computing components.
Exception that is thrown to warn programmers about arithmetic errors in their code.
Also called a list. A data structure that holds a collection of values in a particular order
Arrays are lists that store many values of the same type
Arrays are lists that store many values of the same type
A data structure that stores a **fixed** number of elements, all of the same type, one after another like a list.
The position of an element in an array. The first element is at index 0, the second element is at index 1, and so on.
The number of elements an array can hold. You can get the length of an array `arr` by typing `arr.length`
Returns the length of the array
ArrayList is a Java class that is like an Array with extra powers. It can automatically resize and comes with other helpful methods.
A mutable list of object references. We can create ArrayLists by using the constructor new ArrayList<E>().
A mutable list of object references. We can create ArrayLists by using the constructor new ArrayList<E>().
Accesses an element in the array to either update or retrieve.
the ability of a digital computer or computer-controlled robot to perform tasks commonly associated with intelligent beings
ASCII is the standard protocol for encoding text information as bits. The ASCII table assigns a unique binary number to every text character.
Assigning to a variable is updating the variable's value
One key encrypts, a different key decrypts.
Automatic conversion between primitive types and their corresponding object wrapper classes
The assurance that systems and data are accessible by authorized users when and where needed.
Server devices and applications are often referred to as the “back end” - meaning the user doesn’t actually SEE what is happening; it’s hidden from their view and they just see the results on their end.
Server devices and applications are often referred to as the “back end” - meaning the user doesn’t actually SEE what is happening; it’s hidden from their view and they just see the results on their end.
Command that lets you tell Tracy to move backward. In between the parentheses you need to put a number to tell Tracy how far to move backward.
The capacity of data transfer in a system. Measured by bitrate.
The base case is the simplest form of the recursive problem. The base case can be immediately solved without breaking the problem down any further.
The simplest version of our recursive process. This is the point when the problem cannot be reduced any further.
Drum sounds played sequentially in a repetitive pattern
The actions that can be completed by an object or class.
The behavior of an object is what the object is able to do. It is the actions that can be performed by the object.
Prejudice in favor of or against one thing, person, or group compared with another, usually in a way considered to be unfair.
A way to represent how long an algorithm will take to execute. It helps to determine how efficient different approaches to solving a problem are.
Notation that describes how complex an algorithm is. A larger number inside of the Big-Oh notation means the algorithm takes longer to complete, a smaller number means the algorithm takes less time to complete.
The binary number system is the Base 2 Number System. It is a number system that only uses 2 digits (0 and 1).
Number system that has 2 digits, 0 and 1. This is how computers represent numbers at the base level.
A search that starts at the middle of a sorted array or ArrayList and eliminates half of the array or ArrayList in each iteration until the desired value is found or all elements have been eliminated.
Search algorithm that only works on a sorted list. It discards half of the list on each iteration, getting to the solution much faster than Linear Search.
Bit means "binary digit". A bit is a single digit in a binary number. A bit can either be 0 or 1.
The amount of data (in bits) that can be sent in a fixed amount of time.
attempting to find computer security vulnerabilities and exploit them for personal financial gain or other malicious reasons
Often used when error-based and union-based SQLi do not work. It essentially involves asking the database a series of targeting questions and based on the results gives clues as to how to get the DB to give up its contents.
A True or False value
A boolean is a true or false value.
`boolean` is a Java type that can either be true or false
A framework with predefined web page components that respond automatically to window resizing.
Modeling every element on a web page as if it were wrapped in a box
Exits the current loop and resumes execution at the next statement.
Breaks out of a while loop and executes statements that immediately follow while loop.
Breaking down (decomposing) your code is splitting it into more functions.
Breaking down (decomposing) your code is splitting it up into several smaller, simpler methods
The `break;` statement breaks out of the current loop, without executing any more code in the loop.
The `break;` statement breaks out of the current loop, without executing any more code in the loop.
the overall lightness or darkness of the image
A program on your computer that sends requests for webpages and displays them.
A byte is 8 bits.
An encryption method in which each letter of the message is shifted by a certain amount, called the key
Calling a function actually gives the command, so the computer will run the code for that function.
A method's call site is the point in the code where the method is called.
A function passed as a parameter to another function in order to be called later.
objectName.method()
Calling a method actually gives the command, so the computer will run the code for that method.
A component that continually displays different content, often with the goal of highlighting particular areas or content of the website
Turning something of one type into another type!
Casting is turning something of one type into another type
`char` is a Java type that represents a single character (a single letter)
charAt(int index) returns the character at the specified index.
a group of two or more notes sounded together
a sequence of chords
The CIA Triad is a widely-accepted security measure that should be guaranteed in every secure system. It stands for Confidentiality, Integrity, and Availability.
Science that harnesses the power of many individuals to solve hard, complex problems.
Classes are the template through which objects are created. It is the formal blueprint for creating objects.
A class is a template, or a blueprint, from which Java objects are created. All Java programs start with a class.
`class` is an attribute we can add to HTML tags in order to style a specific group of elements.
Class hierarchy refers to the arrangement of classes and how they relate to each other.
When someone else creates a Class (like `String`, or `Randomizer`), and you are using the functionality of that Class in your program, your program is a *client* of the class. You are using the class as a client.
Client-server applications are programs or apps that run on our client devices AND need to access resources from a server. In other words, they need help and can’t do what they need to do alone.
Client-server applications are programs or apps that run on our client devices AND need to access resources from a server. In other words, they need help and can’t do what they need to do alone.
Client devices are typically personal computing devices with network software applications installed that request and receive information over the network or Internet. Mobile devices like your smart phone, tablets, iPads, laptops and also desktop computers can can all function as clients.
Client devices are typically personal computing devices with network software applications installed that request and receive information over the network or Internet. Mobile devices like your smart phone, tablets, iPads, laptops and also desktop computers can can all function as clients.
Clients and servers communicate over a computer network on separate hardware, but both client and server may reside in the same system. A server host runs one or more server programs which share their resources with clients. A client does not share any of its resources, but requests a server's content or service function. Servers store and protect data and process requests from clients. Clients make requests and format data on the device for the end user.
Clients and servers communicate over a computer network on separate hardware, but both client and server may reside in the same system. A server host runs one or more server programs which share their resources with clients. A client does not share any of its resources, but requests a server's content or service function. Servers store and protect data and process requests from clients. Clients make requests and format data on the device for the end user.
Cloud computing is the on demand availability of computer system resources, especially data storage and computing power, without direct active management by the user.
a collection of images
whenever 2 inputs map to the same output.
the intensity of a color, expressed as the degree to which it differs from white
Command to change Tracy's color.
Command to change Tracy's color.
Command to change Tracy’s color.
A condition in which a person has difficulty distinguishing particular colors from each other
Represents a piece of information (or attribute).
The process of traversing a 2D array by accessing all values at the first column in every row, before moving to the next column
A command is an instruction you can give to Karel.
A message in your code that explains what is going on.
A message in your code that explains what is going on.
Commenting out code makes the computer ignore it, so it does not run.
Algorithms that are often used in computer science to do basic analysis on a list. These often include traversing and selection processing.
The Comparable Interface is a standard interface in Java that mandates that all classes implementing the Comparable interface must define a method called `int compareTo(Object o)` that returns a positive int if the parameter `o` passed in is *less than* the current instance, returns 0 if it is equal, and a negative int if it is greater.
Used to make comparisons between values.
An error in the actual Java code. The code will not **compile** into an executable program, because there are errors in the text of the code.
A tool that compiles your Java code, it takes the Java code you've written and turns it into an executable program.
Colors that create a greyscale color when combined. When placed next to each other, they create the strongest contrast available for those particular colors.
Allows programmers to shortcut variable assignments that include the variable being assigned a new value: x = x + y; shortcut: x += y;
A video, a visualization, a graphic, a program, or an audio recording that students submit providing an illustration, representation, or explanation of the computing innovation's intended purpose, its function, or its effect.
A person or device that makes calculations, stores data, and executes instructions according to a program.
The study of computational thinking, the thinking humans need to in order to describe a step by step process to a computer.
Adding two strings together using the "+" operator.
The process of adding two String values together. This creates a new String object. Primitives can be concatenated with String objects.
The process of adding two String values together. This creates a new String object. Primitives can be concatenated with String objects.
Concatenation is another word for combining. Concatenating Strings is when we add Strings together.
A common error that occurs when attempting to modify an ArrayList while using an enhanced for loop.
A common error that occurs when attempting to modify an ArrayList while using an enhanced for loop.
A common error that occurs when attempting to modify an ArrayList while using an enhanced for loop.
A common error that occurs when attempting to modify an ArrayList while using an enhanced for loop.
The protection of information from people who are not authorized to view it.
A constant is a variable you define at the top of the program that doesn’t change. The reason to define constants is to store named variables that have relevant values for the program.
A constructor is a special method of a Class that constructs a new object (a new instance) of the Class and sets the initial values for the instance variables.
Allows for the creation of a new object. Consists of the constructor name and parameter list.
Rejects all the remaining statements in the current iteration of the loop and moves the control back to the top of the loop to continue to the next iteration. Can be used in both while and for loops.
the difference in brightness between objects or regions
A control structure lets us change the flow of the code.
A coordinate system uses numbers as coordinates to place objects in a geometric space.
A law that grants the creator of an original work exclusive rights to its use, distribution, and sale
A connection between two things.
A method that counts occurrences of specific items in a list.
A variable used to count the number of times an action has been performed
A variable used to count the number of times an action has been performed.
Cross-site scripting (XSS) is a security bug that can affect websites. If present in your website, this bug can allow an attacker to add their own malicious JavaScript code onto the HTML pages displayed to your users. Once executed by the victim's browser, this code could then perform actions such as completely changing the behavior or appearance of the website, stealing private data, or performing actions on behalf of the user.
The process of decrypting coded messages without being told the key.
Scrambling digital information into an unreadable form. Only those with verified authority (password, key, etc) can unscramble it to read it.
The practice of solving and writing encryptions
Cascading Style Sheets. The language for designing web pages and adding style.
the use of electronic communication to bully a person
Identity theft, stealing money, stealing private information, controlling private computers.
Protocols for encrypting/decrypting information. Most cybersecurity breaches happen due to human error, not software bugs.
Protection of computer systems, networks, and data from digital attacks.
An admin-like web page with the functionality to manage the website
Information (numbers, words, measurements, observations, etc) that is in a computer-readable form.
Methods to gather various data points. Surveys, sensors, transactional data from credit cards, websites storing information about you, crowdsourcing data.
The process of encoding information, using fewer bits than the original representation. We can use algorithms to compress the data to use less bits for storage and then decompress it when we want to view it again.
Visualizations can be misleading by skewing the axes or labels, or leaving out relevant data.
how company's use your data
how a company uses your data
The appropriate use of data based on circumstances
protecting your data online
protecting your data online
The integrity, confidentiality, and availability of data
A particular way of organizing data in our programs.
Using charts, graphs, or images to visualize complex data.
Using charts, graphs, or images to visualize complex data.
Using charts, graphs, or images to visualize complex data.
Visualizations can be misleading by skewing the axes or labels, or leaving out relevant data.
An organized collection of data (e.g., text, images, videos, audio, geospatial, tabular) An electronic system that allows data to be easily accessed, manipulated and updated via a Database Management System (DBMS).
An organized collection of data (e.g., text, images, videos, audio, geospatial, tabular) An electronic system that allows data to be easily accessed, manipulated and updated via a Database Management System (DBMS).
Distributed Denial of Service attack. Spam a web server with so many requests so close together that it crashes. Sometimes spitting out valuable information as it crashes.
Rules that show how we can negate expressions with `and` and `or`.
Rules that show how we can negate expressions with `and` and `or`.
Laws that define how we can negate an AND statement and how we can negate an OR statement
!(A && B) == !A || !B; !(A || B) == !A && !B
The decimal number system is the Base 10 number system. It is a number system that only uses 10 digits (0 through 9).
The number system we use in out everyday lives. It has 10 digits, 0-9.
Declaring a variable is defining it for the first time.
Declaring a variable is defining it for the first time.
Decrease the value of a variable by one. variable--;
Defining a function means to teach the computer a new command and explain what it should do when receiving that command.
Defining a method means to teach the computer a new command and explain what it should do when receiving that command.
A data structure to store key/value pairs.
The output from any input that has been processed through a hashing algorithm / function.
The information about a particular person that exists on the Internet as a result of their online activity
A tag that creates a new area of content on a web page that can be styled independently of the rest of the site
A problem solving approach where you **divide** the problem into several smaller sub-problems of similar form, and keep doing so until the problems are trivially simple to solve (**conquer**)
Pretending to be a DNS name resolver. Feed your computer the wrong IP address for a given website, and your browser now goes to a false website.
Documentation is the reference for how to use different methods and classes
Used to translate domain names into IP addresses.
Translates names to IP addresses.
`double` is a Java type that represents a real number with decimal values
Returns the absolute value of a double value
Returns the value of the first parameter raised to the power of the second parameter
The `"` character
Returns a double value greater than or equal to 0.0 and less than 1.0
Returns the positive square root of a double value
Don't repeat yourself: try to simplify your code and avoid repeating code unnecessarily.
Don't Repeat Yourself: Simplify your HTML by grouping code into classes, stylesheets, or other types of templates
Otherwise known as Don’t Repeat Yourself, this principle is designed to help eliminate repeated code and reduce the complexity of a solution
Also called late binding, this refers to Java choosing the proper method to call at run time, as opposed to at compile time.
An edge case is a problem in your code that only occurs in extreme situations.
A control flow tool used as a second condition check after an if statement. It is a contraction of else if.
In the context of an HTML page, inserting outside content into an HTML page
The process of hiding the implementation details of a class from the user
A loop that is an alternate to a for or while loop that accesses each value in an array starting at the first value and proceeding in order.
Variable created in the enhanced for loop header that contains a copy of the array variable.
A physical machine used in WWII that built on the complexity of substitution ciphers.
A triangle where all angles and side lengths are equal.
When two objects have the same properties but are not the same object.
An injection risk where the website returns errors that the hacker can use to explore the database more. This is the first clear test that an attacker can use to test to see if a site is vulnerable. It is usually displayed as an unhandled internal exception error. This info is meant for the developer and is not meant to go back and deliver it to a person’s webpage.
Escape sequences are characters with special meanings.
Enable users to use special characters and actions within String objects.
An event is an action (such as clicking the mouse or pressing a key on the keyboard) that a program detects and uses as input.
determines how the game (or website or app) responds to different events
determines how the game (or website or app) responds to different events
determines how the game (or website or app) responds to different events
user actions or a particular scenario that might trigger an action during a game in video game development (or on a website or app)
user actions or a particular scenario that might trigger an action during a game in video game development (or on a website or app); we say that events are triggered by the user
An exception is thrown by Java when a **runtime error** is encountered. The exception provides information about what kind of error occurred.
Runtime errors in a program. by default, they stop the program.
a piece of software, a chunk of data, or a sequence of commands that takes advantage of a bug or vulnerability to cause unintended or unanticipated behavior to occur on computer software, hardware, etc.
Takes a list as an argument and extends the current list with the list given as an argument.
a computer technology being used in a variety of applications that identifies human faces in digital images
A problem when using a while loop where you forget one action at the beginning or the end.
Able to send bits from router to router across long distances, but they are very expensive.
a software routine that changes the appearance of an image or part of an image by altering the shades and colors of the pixels in some manner
Prevents variables from changing value.
Python method that returns the index at which the string is found in another string, returns -1 if not found.
A firewall is a system that provides network security by filtering incoming and outgoing network traffic based on a set of firewall rules. The purpose of a firewall is to reduce or eliminate the occurrence of unwanted network communications while allowing all legitimate communication to flow freely.
A float, or floating point value, is a numeric value that can have decimal level precision (ex: 3.14)
A float, or floating point value, is a numeric value that can have decimal level precision (ex: 3.14)
A float, or floating point value, is a numeric value that can have decimal level precision (ex: 3.14)
Also called floats, floating point numbers represent real numbers and are written with a decimal point dividing the integer and fractional parts.
A for loop that is written differently so that it loops through each element in a data structure, as opposed to having a loop counter variable that goes from 0 to length-1.
A for loop lets us repeat code a **fixed number of times.**
A for loop lets us repeat code a **fixed number of times.**
A for loop lets us repeat code a **fixed number of times**.
A for loop lets us repeat code a **fixed number of times.**
A for loop lets us repeat code a **fixed number of times.**
A for loop lets us repeat code a **fixed number of times**.
Formal parameters are the parameters outlined in the parameter list in the constructor, while actual parameters are the parameters that are input when a new instance of a class object is created.
Command that lets you tell Tracy to move forward. In between the parentheses you need to put a number to tell Tracy how far to move forward.
Client devices and applications are often referred to as the “front end” - meaning what the user actually sees.
Client devices and applications are often referred to as the “front end” - meaning what the user actually sees.
A function is like a command that you get to invent and name. It allows us to break our program into smaller parts, making the program easier to understand.
A function is like a command that you get to invent and name. It allows us to break our program into smaller parts, making the program easier to understand.
A function is like a command that you get to invent and name. It allows us to break our program into smaller parts, making the program easier to understand.
A function is like a command that you get to invent and name. It allows us to break our program into smaller parts, making the program easier to understand.
In Python functions, the function body is the indented block of code that comes after the `def my_function():` line. The function body is what will be executed when the function is called.
In Python functions, the function body is the indented block of code that comes after the `def my_function():` line. The function body is what will be executed when the function is called.
In Python functions, the function body is the indented block of code that comes after the `def my_function():` line. The function body is what will be executed when the function is called.
In Python functions, the function body is the indented block of code that comes after the `def my_function():` line. The function body is what will be executed when the function is called.
In Python functions, the function body is the indented block of code that comes after the `def my_function():` line. The function body is what will be executed when the function is called.
JavaScript function that returns the height of the graphics canvas
An instance method that allows the client to **get** the value of an instance variable on an object.
JavaScript function that returns the width of the graphics canvas
Graphics Interchange Format; an image format that allows animations
A gigabyte (GB) is 2^30 bytes (1024 MB) of binary data.
A variable that can be used throughout a program, in every scope
One of Bootstrap's layout options that allows the developer to segment the web page into a table of rows and columns in which to place content
A can-do attitude in which a person views challenges and setbacks as ways to learn rather than terminal obstacles in their path to their goal
The physical components of a computer
A relationship between two items that represents an instance variable relationship.
The word hashing literally means to scramble. Hashing changes a message into an unreadable string of text for the purpose of verifying the message’s contents, but not hiding the message itself. It must be easy to compute the output (the digest) for any input, but hard to compute the input for any output. A hash function takes an input string of arbitrary length and produces a fixed- size, short output called a digest . It’s always the same length no matter how big the input is AND the output is always the same hash for any given input. Unlike symmetric and asymmetric algorithms, there are no “keys” in hashing functions.
A data structure that stores key -> value mappings.
Traditionally the very first program you write when learning a programming language, a program that prints "Hello world" to the user.
The hexadecimal number system is the Base 16 number system. It is a number system that only uses 16 digits (0 1 2 3 4 5 6 7 8 9 A B C D E F)
Number system that has 16 digits 1 - 9 and A - F.
Number system that has 16 digits 1 - 9 and A - F.
HTML provides several tags for formatting text on web pages.
Way to organize information with a simple structure that is easy to read and write on a webpage. There are ordered and unordered HTML lists.
Tables display information in a grid.
HyperText Transfer Protocol is a protocol that standardizes the language for talking to web servers to send and receive web pages, or HyperText information (HTML pages).
Protocol that standardizes the language for talking to web servers to send and receive web resources. Defines how computers send and receive hypertext information. (HTTPS: The “S” denotes a secure connection using HTTP.)
Protocol that standardizes the language for talking to web servers to send and receive web resources. Defines how computers send and receive hypertext information. (HTTPS: The “S” denotes a secure connection using HTTP.)
secure data transfer protocol when on the internet
secure data transfer protocol when on the internet
The connection between one HTML page to another HTML page
`id` is an attribute we can add to an HTML tag to style that specific element.
When two variables refer to the same object in memory.
Control structure that lets us do either one section of code or another depending on a test.
An if statement lets you ask a question to the program and only run code if the answer is true.
An if statement lets you ask a question to the program and only run code if the answer is true.
if (boolean expression) { //execute statements if condition is true }
if (boolean expression) { //execute statements if condition is true }
An HTML page embedded inside of another HTML page
A procedure that applies a particular function to an image's pixels to change its appearance
Unable to be changed or manipulated. String are immutable.
Unable to change. Strings in Java are immutable, meaning you can't change it once you make it. If you take a substring of a String, or concatenate something to a String, the result is a *brand new* String, rather than a modification of the original.
When Java automatically casts the value correctly without the programmer needing to do so
The automatic process of transforming a variables data type. This occurs when a primitive and String object are concatenated by changing the primitive value to a String object type.
Keyword that helps in iteration in loops (`for letter in "hello": ...`) or to identify if an iterable (like a list or a long string) contains something (`"h" in "hello"` would evaluate to True).
Increase the value of a variable by one. variable++;
Indentation is the visual structure of how your code is laid out. It uses tabs to organize code into a hierarchy.
Indentation is the visual structure of how your code is laid out. It uses tabs to organize code into a hierarchy.
Array values are stored at a particular index and we access elements in the array by referencing this index value. Index values in Arrays start a 0.
Getting a value at a particular index in an array.
A String object has index values from 0 to length – 1. Attempting to access indices outside this range will result in this error.
A loop that has no way of stopping, and will keep looping forever.
Occurs when the expression in a while loop never evaluates to false. The program continues to run infinitely.
Infinite recursion occurs when the base case can never be reached.
Information literacy is having the ability to find information, evaluate information credibility, and use information effectively.
When a subclass extends a superclass, the subclass inherits all of the static methods, static variables, and public instance methods of the superclass. This is called inheritance.
Initializing a variable is giving it an initial value.
Initializing a variable is giving it an initial value, or a starting value.
A function that prints a prompt and retrieves text from the user.
A sorting algorithm that shifts the already sorted section of an array to place the current array value in the correct index.
Sorting algorithm that sorts an array of values. The idea behind insertion sort is to have a sorted part of the list and an unsorted part. On each iteration of the algorithm, we grab the next unsorted element and place it in its proper position in the sorted section.
A browser's built in functionality that allows the programmer to look at and temporarily modify the code that defines the website
A created object with defined attributes.
Instance is what you call a specific object constructed from a class. Instance and object generally refer to the same thing. An object is a specific instance of a class.
An instance method is a method that defines the behavior of an object. It defines an action that the object can perform.
A variable defined in a Class, for which each object of the class has its own copy.
Used to store the state, or data of the object instances.
Create an instance of a class object.
`int` is a Java type that represents an integer (a whole number)
Returns the absolute value of an int value
Returns a value < 0 if this is less than other; returns zero if this is equal to other; returns a value > 0 if this is greater than other
Returns the index of the first occurrence of str; returns -1 if not found
Returns the value of this Integer as an int and this Double as a double
Returns the number of characters in a String object
These classes are part of the java.lang package and Object class and have a number of useful methods.
These classes are part of the java.lang package and Object class and have a number of useful methods.
When two integers are divided, the decimal values are truncated, or chopped off.
Constructs a new Integer object or a new Double Object that represents the specified int or double value
The highest value Java is able to access. 2147483647
The lowest value Java is able to access. -2147483648
The minimum/maximum value represented by an int or Integer, which are -2147483648 and 2147483647
Aims at ensuring that information is protected from unauthorized or unintentional alteration.
An interface provides a list of methods that *must* be defined if a class chooses to implement the interface.
A philosophy of making information and knowledge open and accessible to ALL. A network of networks built on open, agreed upon protocols.
The Internet of Things (IoT) is the network of physical devices, vehicles, home appliances, and other items embedded with electronics, software, sensors, actuators, and connectivity which enables these things to connect and exchange data.
A protocol that defines the structure of an Internet address and assigns a unique address to every device on the Internet.
Standardizes the layout of all packets. All packets must have a destination IP address, a from IP address, and the actual data being sent. Defines the layout of a SINGLE packet.
Intrusion detection systems (IDSs) are available in two different types: host-based intrusion system (HBIS) and network-based intrusion system (NBIS). An IDS tries to detect malicious activity such as denial-of-service attacks, port scans and attacks by monitoring the network traffic.
the act of switching colors along the color wheel
the act of switching colors along the color wheel (red to green, blue to orange, etc.)
With respect to images, a filter that replaces pixels' color, hue, or brightness with their inverse. The result is light areas become dark and/or colors are replaced with their complementary color
The protocol that defines the payout of an an Internet address.
The protocol that defines the payout of an an Internet address.
A new 128 bit version of the Internet Protocol.
A relationship between two items that represent a superclass / subclass relationship
`islower()` method returns `True` is a string is all lowercase letters and `False` if otherwise.
`isupper()` method returns `True` is a string is all uppercase letters and `False` if otherwise.
Looping through all of the elements of an array
Repetition of instructions a specified number of times, or until a condition is met.
Documentation showing the syntax and examples for how to use the various features of Java.
Includes the class and main method arguments. Must include both in order to run successfully.
A specific standard for commenting Java programs. Javadoc is a format to follow when commenting in order to clearly explain your code.
/** 1. One sentence description of code’s function. 2. Preconditions 3. Postconditions 4. Block tags */
A computer programming language
a computer programming language
a computer programming language
an object-oriented computer programming language commonly used to create interactive effects within web browsers.
Documentation for the syntax and objects in Javascript that we use on CodeHS.
Typically a very large container at the top of a web page that showcases the most important information
Documentation for all Karel Commands and Syntax.
Documentation for all Karel Commands and Syntax
A key is the value used to look something up in a HashMap
A kilobyte (kB) is 2^10 bytes (1024 bytes) of binary data.
The latency of a system is the time it takes for a bit to travel from sender to receiver. Fiber optic cables have low latency.
Command that tells tracy to turn left and in between parentheses, how many degrees to turn left.
An algorithm that searches data sets in a sequential order, checking each value from the 0th index to the end of the data set to see what index a specific element can be located at.
Also called sequential search, a search algorithm that searches for a given value in a list of values. Linear search is less efficient than binary search.
A heterogenous, **mutable** data type that stores an ordered sequence of things.
Also called an array. A data structure that holds a collection of values in a particular order
Python concept used to construct lists in a concise manner.
A Java Interface that represents a general List. The interface provides a list of methods that classes should implement if they want to be used as a List.
The fixed value being assigned to a variable. Often primitive data types.
A variable that is restricted to use in a certain scope of a program
A variable that is defined in a method or constructor. It only exists in the context of the method that it belongs to.
Compares the data of the objects instead of the value of the references. Uses the .equals() method.
Used to make logical associations between boolean values
Used to make logical associations between boolean values.
Can be used to connect boolean expressions to make more complex expression. NOT ! AND && OR ||
Used to make logical associations between boolean values.
A loop, most often set with while(true), that has a break in the loop body.
A loop, most often set with `while(true)`, that has a `break` statement in the loop body.
Throwing away some of the data to save space. We can throw away a lot of data without any noticeable difference from the original.
Python method that changes letters to lowercase.
`lowerCamelCase` is a naming convention where the first letter is lower case, and each subsequent start of a word is upper case.
A number in your code that appears arbitrary. These should all be replaced with calculations or constants.
The Math class is part of the java.lang package and contains only static methods.
Can be manipulated to produce a random int or double in a defined range.
A megabyte (MB) is 2^20 bytes (1024 kB) of binary data.
a humorous image or video that is copied and spread; usually consists of an image and witty caption
Merge sort is a recursive sorting algorithm that can be used to sort elements in an array or ArrayList.
A recursive sorting algorithm that sorts an array of values more efficiently than Selection Sort and Insertion Sort using a Divide and Conquer approach.
a set of data that describes and gives information about other data.
Procedures that allow us to control and define the behavior of an object.
A method is a way to teach the computer a new command
The part of the method that contains the commands
The process of breaking down large problems into smaller problems, each with a method that defines a subproblem in the larger problem.
Methods can have multiple signatures. Java will use the correct signature based on the actual parameters used in a program.
Classes can have multiple methods with the same name, as long as the parameters to those methods are different. Doing this is called "overloading" a method.
If a subclass defines a new method body for a method defined in the superclass, then the subclass has **overridden** the method of the superclass.
A method's **method signature** is the name of the method and the parameter list.
in computer programming languages and especially JavaScript, is the process of removing all unnecessary characters from source code without changing its functionality.
Finds the remainder after division of one number by another (sometimes called modulus). Example: 14 ➗ 4 = 3 remainder 2 14 mod 4 = 2 14 % 4 = 2
Represented with "%" it returns the remainder of the division between two numbers. For example, `14%5` would return 4.
The modulus operator (written as % in most programming languages) divides two numbers and returns the remainder.
An observation that the processing speed of computers is doubling every year. This is *exponential* growth. Computers are getting smaller and faster at an exponential rate.
/* This is a multi- Line comment*/
generated animated imagery based on a piece of music.
A method that enables user to change the value of an object’s instance and static variables.
Methods used to change or manipulate instance variable or object data. Also referred to as setter methods.
Short for `navigation bar`, it contains a series of links that the user can use to visit the main parts of a website
To flip a boolean value, or take the opposite of a boolean value. If you negate true, you get false. If you negate false, you get true.
It is possible to combine more than one of Python's control structures to create more complex programs with various conditions. For example, combining iteration tools like a for loop with conditional statements inside the for loop.
A for loop written, or "nested", inside of another for loop.
A for loop written, or “nested”, inside of another for loop. For example:
A nested function is a function that is defined inside another function. This should be avoided.
The process of placing if statements within if statements.
When a loop is placed within another loop. The total number of runs for a nested loop will be the outer loop * inner loop.
Protocols for data sharing on the internet that define rules and conventions for communication between network devices.
A group of 2 or more computer systems linked together.
Necessary keyword for instantiating a new class object.
Logical operator that negates a single boolean value. Written as `!`. `!a` will be true if `a` is false, and false if `a` is true.
Logical operator that negates a single boolean value. Written as `!`. `!a` will be true if `a` is false, and false if `a` is true.
A keyword that indicates a reference object doesn’t point to any object data.
Before an object variable is initialized, it doesn't point to any memory. It holds a **null pointer**.
The number base of a number system defines how many digits are in the number system, and the base of the exponent for each place value in a number.
Defines how we represent numbers. Which digits we can use, and what each position (place ) in a number means.
Defines how we represent numbers. Which digits we can use, and what each position (place ) in a number means.
A number system defines how we represent numbers. It defines which digits we can use, and what value each position (place value) in a number has.
Also called a dictionary or map. Lets us store pairs of keys that are matched with a specific value.
An object is a variable of a data type that is user defined. Every object has a state and a behavior.
An object is a variable of a data type that is user defined. Every object has a state and a behavior.
An object is a single instance of a Java class. An object has both state and behavior.
The use of object and class types in programming.
Programming model that focuses on **objects** and the data and actions associated with the objects.
The Object class is the superclass of all other classes in Java.
Instance variables can be accessed directly by using the reference variable name + . + the instance variable name. This only works within the class file if the instance variables are set to private.
A triangle where one angle is greater than 90 degrees.
The octal number system is the Base 8 number system. It is a number system that only uses 8 digits (0 through 7).
When a for loop iteration is off by one too many or one too few.
Logical operator that ORs two boolean values. Written as `||`. `a || b` will be true if `a` or `b` is true.
Logical operator that ORs two boolean values. Written as `||`. `a || b` will be true if `a` or `b` is true.
The order in which mathematical expressions should be evaluated. Starts with Parentheses, Exponents, Multiplications and Division, Addition and Subtraction.
When a calculation relies on a number outside the acceptable number range, Java will wrap back to the MIN or MAX value depending on the value.
When a class has more than one constructor with the same name, but different parameter lists.
When a class has more than one constructor with the same name, but different parameter lists.
Override a method occurs when a subclass has the same method signature as a superclass. When a method is overridden, Java uses the method from the subclass.,
Open Web Application Security Project; highly-regarded organization and much used by cybersecurity professionals.
Packages are used to group code into a folder for easy use.
Packages are used to group code into a folder for easy use.
Related classes are grouped together into packages.
Packets are the units of data that are sent over the network.
Taking some variables and packing them into a list.
A variable passed into a method from outside the method.
piece of data provided as input to change the specifics of a program
Pieces of information you can give to functions when you define them. When the function is called the arguments are the data you pass into the function's parameters. Parameter is the variable in the declaration of the function. Argument is the actual value of this variable that gets passed to the function.
The usage of deceptive emails and websites to mailiciously gather personal information
Images are made up of pixels, which are essentially a grid of values. Each value, or pixel, encodes the color at that position in the image.
Images are made up of pixels, which are essentially a grid of values. Each value, or pixel, encodes the color at that position in the image.
An image can be represented as a grid of values. Each value encodes the color at that position in the image.
When an object is assigned to a variable, the variable doesn't hold all of the object's data, it only holds a *pointer* to the object's data. The variable holds a memory location (think of it as a pointer to that memory location), and the object data is stored at that memory location.
Polymorphism is the capability of a method to do different things depending on which object it is acting upon.
An object can take on different forms depending on its implementation. Java can call the correct method even when an object is disguised as a more generic reference type
An object can take on different forms depending on its implementation. Java can call the correct method even when an object is disguised as a more generic reference type
An art movement in the 1950s that is characterized by pop culture imagery such as celebrities and advertisements.
What should be true after a method is called
Conditions that must be true after the code segment is executed.
Assumptions we make about what must be true before the function is called.
Assumptions we make about what must be true before a method is called.
Conditions that must be true prior to execution in order for that code segment to behave as expected.
Primitive types are the basic, simple data types that are inherent to Java (int, double, char, and boolean)
Displaying text on the screen
Print Displaying text on the screen.
JavaScript function that prints out a line to the user
Legal document outlining how a company can collect and use your data
Legal document outlining how a company can collect and use your data
Restricts access to data and methods to the declaring class.
The ability to use methods and programs that we do not fully understand, or are unable to write.
The way your code is written is the style. It covers the aspects of the code that goes beyond whether or not it just works.
A widely agreed upon set of rules that standardize communication between machines.
A set of rules or procedures for transmitting data between electronic devices. In order for computers to exchange information, there must be an agreement as to how the information will be structured and how each side will send and receive it.
A set of rules or procedures for transmitting data between electronic devices. In order for computers to exchange information, there must be an agreement as to how the information will be structured and how each side will send and receive it.
A set of rules or procedures for transmitting data between electronic devices. In order for computers to exchange information, there must be an agreement as to how the information will be structured and how each side will send and receive it.
A model designed to demonstrate the most basic functionality or basic design of a product, sometimes used as a proof of concept
Not actually random, but appears to be random
Allows access to data and methods from classes outside the declaring class.
Class. The name of MyProgram must match the name of the file.
Objects in the public domain are not subject to copyright laws, and thus may be freely used by the general public.
Public key encryption is a type of asymmetric key encryption. There’s one key that encrypts the information and there is a different key that decrypts the information.
Main method. Code to be run must be placed within the main method.
A widely used programming language that is beginner friendly. Google, YouTube, and CodeHS are among the many companies that use Python to build their products.
Let you quickly perform an action on a table in a database like apply changes or retrieve information.
A question (noun) or to ask a question (verb) - often in relation to a database.
Remote Authentication Dial-In User Service (RADIUS) is a client / server protocol and software that enables remote access servers to communicate with a central server to authenticate users and authorize their access to the requested system or service.
The length between the center and edge of a circle
Ransomware is a type cyber attack that threatens to publish the victim's data or block access to it unless a ransom is paid.
Programs that "Read like a story" have good decomposition and make the code easy to follow.
Programs that “Read like a story” have good decomposition and make the code easy to follow.
Java method that lets us read in a true or false value input from the user
Java method that lets us read in a decimal value input from the user
Java method that lets us read in an integer input from the user
Java method that lets us read in a line of input from the user as a String
An iterative process where a method calls itself.
At a high level, recursion is when a function (or method) calls itself.
The recursive case is the general form of the recursive problem. In this case the problem needs to be broken down by one step toward the base case, and the algorithm makes a recursive call to itself to solve this slightly smaller problem. This process repeats until the base case is reached.
When multiple paths exist between two points. This improves reliability and makes the internet fault tolerable. Makes the routing system scalable.
Equality operator (==) compares the references (addresses in memory) of 2 objects
Reference variables store the address of the value
== , !=. <. > , <=, >= These allow for the comparison or primitive type values. The result of these expressions can be stored as a Boolean value.
A website in which the parts of the webpage react and possibly reorder or hide when the window changes size
Exits a function, optionally passing back an expression to the caller. A `return` statement with no arguments is the same as `return None`.
Keyword used in methods to return a value back to the initial program that called the method.
Used to return a value back to the main program from a method.
The `return` statement exits a method and returns a value.
Indicates what type value is being returned from the method
A method's return type is the type of value returned from that method.
The value returned from a function when the function is called.
The value returned from a method.
whenever you can work backwards through an algorithm (like a Caesar cipher)
The RGB encoding scheme allows us to encode colors such as numeric data. It defines the amount of Red, Green, and Blue light in a pixel.
The RGB encoding scheme allows us to encode colors such as numeric data. It defines the amount of Red, Green, and Blue light in a pixel.
A triangle that includes one 90 degree angle.
Command that tells tracy to turn right and in between parentheses, how many degrees to turn right.
The process of sending data between two computers on the internet. The data is sent through routers that determine the route.
One entry in a table. Each row has an ID that is unique to the table.
One entry in a table. Each row has an ID that is unique to the table.
The process of traversing a 2D array by accessing all elements in a row before moving on to the next row.
The ordering of 2D arrays is row-major order, meaning the first index is the row, and the second index is the col. `arr[2][0]` would access the element on the third row and first column.
An error that happens while the program is running. Even if the code is written with the proper syntax, there are things that can go wrong while the program is running.
A class within java.util. It contains code specifically designed to help with user input.
A class within java.util. It contains code specifically designed to help with user input.
one image in a series of images that make up a GIF
How we define what is stored in a table.
Defines which part of the program a variable can be accessed from.
A statement in SQL that allows you to ask for a row or multiple rows from a table in a database. SELECT * FROM House; (SELECT and FROM are key words, meaning they can’t be used for anything else like table names, column attributes, etc.) * chooses every column in the table; House is the name of the table SELECT name FROM House (returns the House table with only the name column) SELECT name, id FROM House (returns the House table with the name and id columns)
A statement in SQL that allows you to ask for a row or multiple rows from a table in a database.
Using a condition to determine which part of an algorithm is executed.
A sorting algorithm that swaps the minimum value left in an array with the current array index.
Sorting algorithm that takes an array of values and sorts it. The idea is to have a sorted part of the list and an unsorted part. On each iteration, selection sort finds the lowest value in the unsorted section of the list and adds it to the end of the sorted part.
Defines which HTML elements a CSS rule applies to.
A constant that has the specific purpose of being the value that breaks out of a loop.
A constant that has the specific purpose of being the value that breaks out of a loop.
Sequencing, or sequential execution, is step by step execution of instructions in the order they are given.
A search technique that starts at the first element and goes through each element until it finds the target value.
A server computer program or application provides functionality for client programs or devices. So a single overall computation is distributed across multiple processes or devices. Servers can provide various functionalities, often called "services", such as sharing data or resources among multiple clients, or performing computation for a client.
A server computer program or application provides functionality for client programs or devices. So a single overall computation is distributed across multiple processes or devices. Servers can provide various functionalities, often called "services", such as sharing data or resources among multiple clients, or performing computation for a client.
Examples of servers include web servers, mail servers, and file servers. Each of these servers provide resources to client devices. Most servers have a one-to-many relationship with clients, meaning a single server can provide multiple resources to multiple clients at one time.
Examples of servers include web servers, mail servers, and file servers. Each of these servers provide resources to client devices. Most servers have a one-to-many relationship with clients, meaning a single server can provide multiple resources to multiple clients at one time.
A data structure that stores values in no particular order. Each value can only appear once in the set.
An instance method that allows the client to **set** the value of an instance variable on an object.
If two variables within the same scope have the same name, the variable with the more specific scope will be called.
When the result of a logical expression using && or || can be determined by evaluating only the first Boolean operand, the second is not evaluated.
A short cut when evaluating boolean expressions. If the result can be determined solely by the first part of a boolean expression, the second part is not evaluated, it is skipped.
//This is a single line comment
Accessing specific chunks of a string.
Programs that can be run on a computer
To arrange a list of values in order from least to greatest (or greatest to least).
A tag that creates an inline area of content on a webpage that can be manipulated separately from the block it is enclosed in
Structured Query Language; Programming language for managing and querying data from a relational database.
Structured Query Language; Programming language for managing and querying data from a relational database.
Structured Query Language; Programming language for managing and querying data from a relational database.
refers to an injection attack wherein an attacker can execute malicious SQL statements (also commonly referred to as a malicious payload) that control a web application's database server (also commonly referred to as a Relational Database Management System – RDBMS).
The data that is associated with an object or class.
The state of an object is all of the object's associated data. It is the *state* that the object is in.
The number of times a statement is executed by the program.
A method called on the Class, rather than on a specific object of the Class.
Static methods are the methods in Java that can be called without creating an object of class. Static methods are called using the dot operator along with the class name unless they are defined in the enclosing class.
Static methods are the methods in Java that can be called without creating an object of class. Static methods are called using the dot operator along with the class name unless they are defined in the enclosing class.
Methods that can be used directly by the class name. They cannot access instance variables or non-static methods.
A variable or attribute of a class that is shared between **all** instance of a class. Each instance **does not** get their own copy.
Variables that can be accessed by all objects of a class. They are called using the class name, and can be used in static and non-static methods.
Variables that can be accessed by all objects of a class. They are called using the class name, and can be used in static and non-static methods.
The art and science of concealing secret messages in such a way that no one apart from the intended recipient knows about the existence of the message. In digital information, Steganography is the practice of concealing a file, message, image, or video within another file, message, image, or video.
String is a Java type that represents a string of characters (text)
Strings cannot be mutated or changed.
Accessing certain characters in a string.
A sequence of characters enclosed in double quotations “ “.
Accessing specific chunks of a string.
Returns substring(from, length())
Returns the substring beginning at index from and ending at index to − 1
Constructs a new String object that represents the same sequence of characters as str
Constructs a new String object that represents the same sequence of characters as str
Python method that returns a copy of the string you call it on, without any whitespace at the beginning or end.
Allows adding several different types of styles to HTML elements.
If a class A extends the class B, then A is a subclass of B.
A child class that inherits attributes and behaviors from a superclass (parent).
A substring is a smaller sequence of characters in a larger String.
The `super` keyword lets us reference the superclass when writing code inside of a subclass.
A Java keyword used to refer to the superclass object. In this lesson we saw it used to call the superclass constructor.
A Java keyword used to refer to the superclass object. In this lesson we saw it used to call the superclass constructor and other methods from the superclass.
Super Karel is still Karel, but it knows two new commands: `turnAround()` and `turnRight()`
A parent class that contains common attributes and behaviors used by subclasses (children).
If a class A extends the class B, then B is the superclass of A.
SuperKarel is like Karel but already knows how to turnRight() and turnAround()
The same key is used to encrypt and decrypt (e.g., Caesar, Vigenere)
The same key is used to encrypt and decrypt (e.g., Caesar, Vigenere)
An error in the sequence of words or rules in a program that prevents the program from running.
When all programs and code will work as intended.
Displays output on the computer monitor.
Java method that lets us print output to the user, without ending the line printed.
Displays output on the computer monitor and moves cursor to next line.
Java method that lets us print out a line of output to the user
A set of data elements (values) using a model of vertical columns (shown by a name) and horizontal rows (fields), the cell (record) being the unit where a row and column intersect. A table has a specified number of columns by design, but can have any number of rows.
A set of data elements (values) using a model of vertical columns (shown by a name) and horizontal rows (fields), the cell (record) being the unit where a row and column intersect. A table has a specified number of columns by design, but can have any number of rows.
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The run method is where a Java program begins.
The `this` keyword is a reference to the current object (the current instance).
Makes a call to the current object in a class file. Allows programmers to specify which objects and instance variables should be called.
A small box with extra information about an element that appears when the cursor hovers over the element.
Top down design is a method for breaking our program down into smaller parts.
Top down design is a method for breaking a problem down into smaller parts.
toString is a special method you write in your class that returns a String representation of the object.
A specific accessor method that returns a String value with information about an object’s instance values. This overrides the object’s inherit toString method when an object is printed using System.out.print or System.out.println
Allows for sending MULTIPLE packets between two computers. TCP checks that all packets arrived and can be put back in the proper order. The metadata must include a destination IP address, a from IP address, the message size and the packet order number.
Traversing an array is the process to loop through an array and access each of the elements. Caution must be taken to avoid looping beyond the valid index values.
The structure of an HTML document
Not starting the y-axis at zero.
A truth table is a table used in logic for comparing Boolean expressions.
A truth table is a table used in logic for comparing Boolean expressions.
Programming constructs that can be used to gracefully handle exceptions so that a program can continue in spite of them.
A heterogenous, immutable data type that stores an ordered sequence of things.
The type of a variable defines what kinds of values the variable can hold
Ultra Karel is the same as Super Karel, except Ultra Karel has the ability to paint the grid world!
Reverse of autoboxing; automatic conversion from the wrapper class to the primitive type
An injection risk where the attacker can add a condition that’s always true, like 1=1, often by appending it to the query to pull up even more in a results set. This fundamentally changes the query and can allow someone to pull the entire contents of the database.
Unpack some variables from a list.
Python method that changes letters to uppercase.
Stands for Uniform Resource Locator. You are locating a resource that exists somewhere on the internet.
A particular sequence of actions that a user takes to accomplish a particular task
The tools, visual aids, and other components available to a user in order to interact with a web page or other digital or mechanical device
An adjective that generally is used to describe a UI that is intuitive to use, easy to navigate, and allows the user to quickly and efficiently complete the desired task
The value is the result you get when you look up a key in a HashMap. It is the value paired with a key.
A symbol or container that holds a value.
If two variables have the same name, and exist inside of the same scope, the variable with the *more specific* scope takes precedence. This is called shadowing. Local variables and parameters shadow the more general global variables (instance variables).
Allows users to input double values.
Allows users to input int values.
Allows users to input String values.
An encryption method that uses a series of interwoven Caesar ciphers based on the letters of a keyword
An attribute that determines if a particular element can be seen by the viewer of the web page
Visibility (usually `public` or `private`) defines who has access to something (usually a variable or method). Public means code outside of the class can access, private means only code inside the class can access.
a weakness which can be exploited by a malicious actor / attacker to perform unauthorized actions within a computer system.
Standardized widgets on a website that bundle the actual implementation details into reusable elements
Designing web page to make it appealing and easy to use for viewers
Writing the HTML, CSS, and other code to actually generate a web page
A document that can be viewed by a web browser, usually written in HTML
A collection of related webpages, usually registered under the same domain name
a clause in SQL that allows you to filter results of s SELECT with certain conditions.
a clause in SQL that allows you to filter results of s SELECT with certain conditions.
Lets us repeat code as long as something is true.
a computer security specialist who breaks into protected systems and networks to test and asses their security
a computer security specialist who breaks into protected systems and networks to test and assess their security
Objects are defined by having the attributes, or instance variables that they are assigned.