A static inner class is a nested class which is a static member of the outer class. It can be accessed without instantiating the outer class, using other static members. Just like static members, a static nested class does not have access to the instance variables and methods of the outer class.

What is a static class?

A static class is similar to a class that is both abstract and sealed. The difference between a static class and a non-static class is that a static class cannot be instantiated or inherited and that all of the members of the class are static in nature.

What is the use of static class?

The advantage of using a static class is that the compiler can check to make sure that no instance members are accidentally added. The compiler will guarantee that instances of this class cannot be created. Static classes are sealed and therefore cannot be inherited. They cannot inherit from any class except Object.