Adding an Assembly to the Global Assembly Cache : Assembly « Development « ASP.NET Tutorial

All the assemblies that make up the .NET Framework class library are contained in the Global Assembly Cache. 
Any assembly located in the Global Assembly Cache can be referenced by any application running on a server.

The Global Assembly Cache's physical location is at the following path:

C:\WINDOWS\assembly

Before you can add an assembly to the Global Assembly Cache, you must add a strong name to the assembly. 
A strong name is similar to a GUID. You use a strong name to provide your assembly with a universally unique identifier.

You can generate a strong name by using the sn.exe command-line tool like this:

sn.exe -k KeyPair.snk

Executing this command creates a new file named KeyPair.snk, which includes a new random public/private key pair.

You can compile an assembly that includes a strong name by executing the Visual Basic .NET command-line compiler like this:

csc /t:library /keyfile:KeyPair.snk /recurse:*.cs /out:MyLibrary.dll

9.3.Assembly
	9.3.1.	Building Component Libraries by Using the C# Command-Line Compiler
	9.3.2.	Make an assembly available to an ASP.NET application
	9.3.3.	Adding an Assembly to the Global Assembly Cache
	9.3.4.	Building Basic Components
	9.3.5.	Components and Dynamic Compilation
	9.3.6.	Mixing Different Language Components in the App_Code Folder
	9.3.7.	Declaring Methods
	9.3.8.	Declaring Fields and Properties
	9.3.9.	Component with Property
	9.3.10.	Adding comments to a component.
	9.3.11.	Using ASP.NET Intrinsics in a Component
	9.3.12.	Load server side assembly