assemblies are of two types, They are Shared assembly and 
private assembly. shared assemblies are shared among 
multiple applications and they are stored in Global 
Assembly Cache. Private Assemblies implies to a single 
application and they are stored in the root directory of 
the application.

Please note there are three types of Assemblies.

1) Private - Assembly available only to clients in the same 
directory.
2) Shared - Assemblies in GAC
3) Satelite - Assembly in the specific directory of the 
locale.

1.assemblies is unit of deployment like exe dll
assemblies information is stored in Manifest where all 
details of assemblies are include.
This manifiest is stored in PE file that is protable 
executable fime we can view assemblies using ILDASM.

2.types
 private
 shared
private assembly is used for single application which is 
stored in application directory.

shared assembly is which is used by many users.and that is 
stored in (GAC) that is Global Assembly Cache where 
adminstrator can make rights on them and he is only one 
person where he can add or remove it.

1.assemblies is unit of deployment like exe dll
assemblies information is stored in Manifest where all 
details of assemblies are include.
This manifiest is stored in PE file that is protable 
executable fime we can view assemblies using ILDASM.

2.types
 private
 shared
private assembly is used for single application which is 
stored in application directory.

shared assembly is which is used by many users.and that is 
stored in (GAC) that is Global Assembly Cache where 
adminstrator can make rights on them and he is only one 
person where he can add or remove it.

Assembly is Basic Unit Application Deployment in .Net. This 
is either DLL or EXE.We have 3 types of Assemblies in .Net
1.Private Assembly:This is Local to Perticular Application 
and not sharable among all the applications.This will be 
stored on application Root directory.
2.Shared Assembly:This is Sharable among all the 
applications in our System.This will Stored in Global 
Assembly Cache.
3.Sattelite Assembly:This is not having appliaction having 
only Language Specification.

Assembly having 3 Types:
1) Private: only for single application.
it will be stored in local Root Directory.
2)Shared: Shared b/w more then one Application.
Stored in GAC(Global Assembly Cache).
3)Sattelite:This is uesd for Localization of Language.
(Localization means Translating)

*Single and Multi-File Assemblies:
There are several ways to group the various elements in an 
assembly. You can group all elements (manifest, MSIL and 
resources) in a single physical file or group them 
separately in several files. An assembly that groups all 
elements in a single file is called a single file assembly, 
whereas the assembly that groups its elements in multiple 
files is called a multi-file assembly.

A single-file assembly can be created by compiling the 
application in Visual Studio .NET. The Visual Studio .NET 
IDE for Visual Basic can only be used to create single-file 
assemblies. Multifile assemblies can be created using 
command-line compilers.

*Private and Shared Assemblies:
Private assemblies are those assemblies that are accessible 
only to the applications residing in the same directory as 
that of the assembly. When you create an assembly, it is 
private by default. No other application can make use of 
private assembly. For a private assembly to be accessible 
by more than one application, you must copy the files of 
the assembly separately into the folder in which the other 
application resides.

Shared assemblies are assemblies added to the GAC (Global 
Assembly cache). GAC is used to store assemblies and to 
share them between multiple applications. IN the shared 
system, the names of the assemblies should be unique as it 
can be accessed by all applications. The newer versions of 
the component should also have unique names. These can be 
achieved by using a strong name for the assembly. A shared 
assembly is placed in the GAC folder that is reserved for 
shared assemblies.