Inheritance is a mechanism in Java that allows one class to inherit the properties and methods of another class. It is a way to create a new class that is a modified version of an existing class, without having to rewrite the entire class from scratch.

To use inheritance in Java, you use the extends keyword in the class declaration to specify the class you want to inherit from. For example:

class Animal {
  // properties and methods of the Animal class
}

class Cat extends Animal {
  // properties and methods of the Cat class
}

In this example, the Cat class is the subclass and the Animal class is the superclass. The Cat class inherits all of the properties and methods of the Animal class, as well as any properties and methods that are specific to the Cat class.

One of the main benefits of inheritance is that it allows you to reuse code, which can make your program more efficient and easier to maintain. It also allows you to create a hierarchy of classes, where a subclass can inherit the properties and methods of a superclass and then add additional functionality on top of it.

There are some rules to follow when using inheritance in Java:

• A class can only extend one superclass, but a superclass can have multiple subclasses.
• A subclass can override the methods of its superclass by providing a new implementation for the method.
• A subclass can also access the non-private methods and properties of its superclass using the super keyword.