Java | Variables: Variables are using to store the data. Details of Variables: Variable Declaration and Initialization: Create the variable and assign the value to it. Ex: int i = 1. Modification of Variables: Variables can modify by doing operators on them. Ex: i = i + 2. Types of Variables: Variable types are integer, string, float/double and boolean. Ex: 1 is integer, "Java" text with double quotes is string, 1.43 number with decimal values are float/double and true/false is boolean. Here is the Code: import java.io.*; class Main { public static void main (String[] args) { // Declaration and Assigning int i = 1; System.out.println(i); // Modification i = i + 2; System.out.println(i); // Types double j = 1.43; System.out.println(j); String s = "Java"; System.out.println(s); boolea