Assembly are the basic building blocks of .net
Three type of assembly are there.
1. Private Assembly
2. Shared Assembly
3. Satelite Assembly.
GAC is used to provide the different versioning.
Strong name used to use it without any complication or 
fault.

In the Microsoft .NET framework, an assembly is is used by
the .NET CLR (Common Language Runtime)as a partially
compiled code library for use in deployment, versioning and
security. In the Microsoft Windows implementation of .NET,
an assembly is a PE (portable executable) file. There are
two types: process assemblies (EXE) and library assemblies
(DLL). A process assembly represents a process which will
use classes defined in library assemblies.
Assemblies consists of a manifest and one or more modules
and/or files like HTML, XML, images, video clips,...

An assembly  must contain a single manifest and may
optionally contain type meta data, MSIL (Microsoft
Intermediate Language) and resources.

.Net Assembly can be classified in four Categories:

  (A)  With Respect to  Program Access.
          i) Private Assembly- It can be used only in one
application.This is the default style of assembly. Such
assemblies must reside in the application folder.
         ii) Public/Shared Assembly- It can be used by all
applications in the server. 
They must have a globally unique name and must be defined in
the GAC (Global Assembly Cache).

  (B)  With Respect to Number of Resources.
          i) Static Assembly- It uses fixed resources.
         ii) Dynamic Assembly- It supports dynamic creation
of resouces or files at    
             runtime programatically.

  (C) With Respect to Deployment.
         i) Satellite Assembly- Easily Deployable. (Visual
Studio 2005).
        ii) Resource-Only Assembly- In Visual Studio 2003.

  (D) With Respect to Number of Assemblies.
         i) Single File Assembly- /Bin/x.dll

        ii) Multi File Assembly- /Bin/x.dll
                                                   y.dll
                                                   z.dll  
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