Learn Java Programming: Variables and Data Types

Variables are places where temporary values ​​are stored.

Just that.

Are you serious?

Yes seriously, if you want a longer one...

…let's see what it means from Wikipedia:

Variables: (Lat) 1. variable, not fixed; 2. declaration of something that has a variety of values ​​3. different in programming languages ​​are also called symbols that represent certain values, variables known in sub programs are called local variables. being known in general / intact in one program is called a global variable.

Well, don't you know?

Otherwise, just understand: Variable as a place to store temporary values.

Then, what is a data type?

A data type is a type of data stored in a variable.

Various Data Types
The following are the various data types in Java:

▶️ char: Character data type, example Z
▶️ int: number or integer, example 29
▶️ float: decimal number, example 2.1
▶️ double: decimal number too, but larger capacity, example 2.1
▶️ String: a collection of characters that make up text, eg Hello World!
▶️ boolean: a data type that only evaluates to true and false.

Creating Variables

The thing to know in creating variables in java is how to write them.

The format is like this:

Example:

Create an empty variable of type integer:

Create a variable of type integer and directly fill in the value:

Create a set of variables of the same data type:

So, where is it written?

Inside the main() function: the variables written in the main() function and other functions are called local variables.
Inside the class: These variables are called class or global variables.