.NET components or Assemblies or User Defined Class Libraries or DLL

• A component is reusable piece of code and is in the form of DLL
• Once component is designed it can be reused from any kind of application like in console application or windows application or web application or device application etc
• Once a component is designed in any programming language of .Net that can be reused from other programming languages of .Net i.e. .Net components or  assemblies will provide language interoperability
• To create computer in .NET, we use class library templates
• End user will never interact with DLL or component directly
• Always end user will interact with some application and the application will interact with component or DLL