What is the difference between class and variable in Java?

In Java, a class and a variable are distinct concepts with different roles:

Class: A Blueprint for Objects

A class serves as a blueprint for creating objects. It defines the attributes (variables) and methods (functions) that objects of that class will possess. Think of it like a cookie cutter: the class defines the shape and size of the cookie, while the objects are the actual cookies created using that cutter.

Example:

class Car {
    String model;
    int year;

    void start() {
        System.out.println("Car started!");
    }
}

In this example, Car is a class that defines the attributes model and year and the method start. We can create objects of type Car using this class.

Variable: A Data Container

A variable is a container that holds a value of a specific data type. It acts as a placeholder for data that can be used and modified within a program.

Example:

int age = 25;
String name = "John";

Here, age and name are variables. age holds an integer value of 25, while name holds a string value "John".

Key Differences

Summary

In essence, a class provides the structure for creating objects, while a variable stores data within those objects. They work together to define and manipulate data within a Java program.