Understanding Variables and Data Types in Java

 

🧠 What Is a Variable?

Think of a variable as a container that stores data. It could be a number, a word, or even a true/false value.

Common Data Types In Java

Data Type            Example                    What it stores
int                        int age = 15;              Whole Numbers

double                 double d = 1.2;          Decimal Numbers

String                  String s = "TOM";     Text(Always in quotes)

boolean               boolean i = true;         True or False

char                     char grade = 'A';         A single character(in single quotes)

//Sample Code

public class VariableDemo {

    public static void main(String[] args) {

        int age = 15;

        double score = 95.5;

        String name = "Aarav";

        boolean isCool = true;

        char grade = 'A';

        System.out.println("Name: " + name);

        System.out.println("Age: " + age);

        System.out.println("Score: " + score);

        System.out.println("Cool? " + isCool);

        System.out.println("Grade: " + grade);

    }

}

//output

Name: Aarav  

Age: 15  

Score: 95.5  

Cool? true  

Grade: A