Assembly in asp.net

Assembly :- Assemblies are the building blocks of .NET Framework applications; they form the fundamental unit of deployment, version control, reuse, activation scoping, and security permissions Assembly is unit of deployment like EXE or a DLL.

 OR

An assembly consists of one or more files (dlls, exe's, html files etc.), and represents a group of resources, type definitions, and implementations of those types. An assembly may also contain references to other assemblies. These resources, types and references are described in a block of data called a manifest. The manifest is part of the assembly, thus making the assembly self-describing.

An assembly is completely self-describing.An assembly contains metadata information, which is used by the CLR for everything from type checking and security to actually invoking the components methods. As all information is in the assembly itself, it is independent of registry. This is the basic advantage as compared to COM where the version was stored in registry.

There are two types of assembly

 Private and Public assembly. Private assemble :- A private assembly used in single application and is stored in the application's directory, or a sub-directory beneath.  The dll or exe which is sole property of one application only. It is generally stored in application root folder    

 Public assembly/Shared assembly : - A shared assembly is normally stored in the global assembly cache, which is a repository of assemblies maintained by the .NET runtime.
It is a dll which can be used by multiple applications at a time. A shared assembly is stored in GAC