An Assembly is a fundamental unit of Deployment. In ASP.NET, the assembly is the process of packaging contain .exe, .dll & .lib (library files) created by default which contain complied code of some commonly used functions whenever you build a DLL. “ Assemblies are the basic fundamental building blocks for Dot.net framework. Assembly contains one or multiple files either dll or exe...actually assembly was created whenever dll built “Two Types of assembly 1) Private Assemblies , 2) Shared Assemblies1) Private ASP.NET Assemblies are created when you build component files like DLLs that can be applied to one application. 2) Shared ASP.NET Assemblies are created when you want to share the component files across multiple applications.