How many types classes in C sharp?

There are four types of classes in C# .Net 1) Abstract class - An Abstract Class means that, no object of this class can be instantiated, but can make derivation of this. It can serve the purpose of base class only as no object of this class can be created. Abstract Class is denoted by the keyword abstract. 2) Partial class - Partial Class allows its members – method, properties, and events – to be divided into multiple source files. At compile time these files get combined into a single class. 3) Sealed class - A sealed class is a class which cannot be inherited. A sealed class cannot be a base class. The modifier abstract cannot be applied to a sealed class. By default, struct (structure) is sealed. It is the last class in hierarchy. To access the members of a sealed class, you must create objects of that class. Sealed Class is denoted by the keyword sealed. 4) Static class - A Static Class is one which cannot be instantiated. The keyword new cannot be used with static classes as members of such class can be called directly by using the class name itself. read less