Question

What is an abstract class?

Answer 1

$\huge\bold{Abstract\:Class}}$

in programing languages,an abstract type is a nominative type system that cannot be instantiated directly. every instance of an abstract type is an instance of some concrete subtype.

Answer 2

$\bold{Abstract\:classes}$ are classes that contain one or more abstract methods.

An abstract method is a method that is declared, but contains no implementation. Abstract classes may not be instantiated, and require subclasses to provide implementations for the abstract methods.