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Java Variables and Data Types

   Variables in Java

Variables are the containers to store the data values in the memory. Variables are naming entities and must follow naming conventions. These rules typically include starting with a letter or underscore, using letters, numbers, or underscores (no spaces or special characters), avoiding reserved keywords, and using naming conventions such as CamelCase or snake_case for readability. These conventions help keep the code organized and understandable.
        

            Syntax:

                            data_type    variable_name;
                            data_type    variable_name    =    value;

        Examples:

                            int myAge = 21;
                            String myName = "Zack";

Data Types in Java

When declaring a variable, it's essential to specify the type of data it will store, such as numbers or words. These specifications are known as data types. 

There are two data types: 

  1. Primitive Data Types:   byte, short, int, long, float, double, boolean and char
  2. Non-primitive Data Types:  String, Arrays, and Classes




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