WEBVTT

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alright welcome back in this video

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you'll learn about something that is a

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fundamental aspect of just about every

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programming language variables let's

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dive in and look at a program that has a

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variable in it in a minute we'll take

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some time to go over exactly what a

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variable is and what it does the

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variable in this program is called

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greeting it has a value which is hello

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world this means that printing greeting

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is basically the same as printing hello

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world

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here's another program with a variable

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the variable is called my number and its

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value with the number 50 okay so what is

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a variable a variable is something that

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stores information in a program so that

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it can be used later that information

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can be something like hello world or the

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number 50 more specifically a variable

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has three things a name a type and a

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value so let's look at the two variables

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that we just saw and spell out each of

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these three characteristics in the case

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of the variable greeting the name of the

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variable is greeting the type of the

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variable is ster which I'll explain in a

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second and the value is hello world in

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quotes

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note that when you print the variable

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greeting you don't put quotes around it

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then we saw a variable whose name was my

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number whose type was int which I'll

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also explain in a second and whose value

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was 50 okay so what did these types mean

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stur is short for string a variable

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whose type is ster contains text or a

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sequence of zero or more characters and

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these characters can be letters numbers

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punctuation spaces whatever you can type

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on your keyboard so hello world is an

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example abc123 is an example or a string

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can actually have zero characters okay

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quick digression strings can also be

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surrounded by single quotes in Python

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however in this course we will use

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double quotes now let's look at the type

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int int is short for integer and a

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variable whose type is int contains a

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number and that number can be positive

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negative or zero however it cannot have

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a decimal component so negative 50 0 and

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5 are all examples of integers another

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type that we haven't seen yet but we

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will in future lessons is float float is

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short for floating point number and this

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is basically like an integer except it

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does have a decimal component so

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negative three point two zero point zero

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or four point five six five two are all

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examples of

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note that the decimal component can be

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zero so zero point zero is in fact equal

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to the integer zero you can create a new

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variable or update an existing variable

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in Python using what's called an

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assignment statement this statement has

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three parts on the left you have the

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name of the variable on the right you

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have the value that you want to give to

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that variable and in the middle you just

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have a single equal sign