Check out example codes for "variable name in java". It will help you in understanding the concepts better.

Code Example 1

int // int is a variable the stores numbers
string // a variable for storing text

Code Example 2

Java variable names are case sensitive. ...
Java variable names must start with a letter, or the $ or _ character.
After the first character in a Java variable name, the name can also contain numbers (in addition to letters, the $, and the _ character).

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