In Java, abstract means incomplete . It is used when a class or method is not fully finished and child classes must complete it. Abstract Class A class declared with abstract keyword is called an abstract class. abstract class Animal { } Enter fullscreen mode Exit fullscreen mode Cannot create object directly Mostly used as parent class Animal a = new Animal (); // ❌ Error Enter fullscreen mode Exit fullscreen mode Abstract Method An abstract method has: only declaration no body abstract void sound (); Enter fullscreen mode Exit fullscreen mode Child class must implement it. Example abstract class Animal { abstract void sound (); } class Dog extends Animal { void sound () { System . out . println ( "Bark" ); } } Enter fullscreen mode Exit fullscreen mode Here: Animal gives only idea Dog completes the method Simple Real-Life Example Think about a “Vehicle”.…