WEBVTT

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hi in this video we're going to talk

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about variables so what's a variable a

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variable is like a box with a name that

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can hold a value so here I have a

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variable called num apples with the

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value 5 that represents these five

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apples here

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so remember variables have a name a type

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and a value so in this example the name

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is num apples the type is int for

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integer and the value is 5 there's five

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apples so there's a few important things

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we can do with variables and one of them

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is declaring a variable so this code

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here int number semicolon declares the

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variable num Apple so what that really

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means is that you're saying I hereby

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make a box called num apples to hold an

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integer so it's important that you in

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Java you say the type of the variable

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when you declare it so the other

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important thing is initializing a

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variable so here with this code we're

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creating the variable num apples and

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initializing it to five so initializing

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both is creating the variable and

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setting its initial value so here you

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see the Box now apples has the value

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five and assigning to a variable lets us

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actually change the value in the box so

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here on this first line I write int

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number plus Eckles five that initializes

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the variable num apples to five and then

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this next line num apples equals zero

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that sets the value in the box equal to

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zero it assigns a new value to the

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variable and there's something really

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important on this line notice that I

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don't have the word int again you only

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write the word int or the type of the

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variable when you declare the variable

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for the first time so there's a few

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types in Java that you'll want to be

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aware of some of them are the primitive

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types and so we've already used int

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which is for integers double is for

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numbers that have decimals care is for

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characters like a B

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GED and boolean is for true/false values

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so for the number types the integers are

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whole numbers the numbers used to count

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you know numbers like negative three

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negative two negative one so here is an

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example of using integer int num a

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police file doubles they're like real

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numbers and they can have decimals so

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for example double cost equals forty

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point two five the boolean type

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represents a true/false value so boolean

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logged in equals false and boolean game

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over equals true and the care type

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represents a single character like care

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first letter equals a and care grade

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equals B and notice that with cares were

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just writing these between single quotes

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another type you'll want to know is

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called string strings are not a

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primitive type like the others and

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strings are for text so string is go

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between quotes and start with a capital

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S remember it's not a primitive type

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like the others so if I want to write a

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variable to save my name I write string

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name equals and then in double quotes

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Jeremie string question equals how are

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you