Sealed class and abstract class in C#.NET and VB.NET

Sealed Class:

A sealed class is a class the does not allow inheritance . Means you can not inherit the sealed class . In VB.NET sealed class is represented as Non Inheritable class.

Abstract class:

Abstraction is process of identifying common patterns that have semantic variations . An abstraction represents the common patterns and provide means of variations you can use.

Abstract class methods does not have implementation. It just contain a structure.

Abstract class is equivalent to must inherit class in vb.net