<P> In the Java programming language, a keyword is one of 53 reserved words that have a predefined meaning in the language; because of this, programmers cannot use keywords as names for variables, methods, classes, or as any other identifier . Due to their special functions in the language, most integrated development environments for Java use syntax highlighting to display keywords in a different colour for easy identification . </P> <Dl> <Dt> abstract </Dt> <Dd> Abstract is used to implement the abstraction in java . A method which doesn't have method definition must be declared as abstract and the class containing it must be declared as abstract . You can't instantiate abstract classes . Abstract methods must be implemented in the sub classes . You can't use abstract keyword with variables and constructors . In an abstract class, you can keep abstract method (without body) and non-abstract method (with the body). By the help of abstract keyword, we can make any class as abstract . </Dd> </Dl>

Which is the reserved word in java programming language