Private and Shared assemblies

Private assemblies:- The scope of private assemblies is upto that application in which folder it resides (.dll file in bin folder). for example I have my own customize PaymentGateway.dll in my ecommerce web application bin folder then i can user paymentgateway functionality only in my ecommerce webapplication not in other webapplication on server.
 
Shared assemblies:- The scope of shared assemblies is upto all application in server. for example crystal report .dll when you install it will reside in Global Assembly Cache. so all web application of that server can use crystal report functionality.

1) Private assembly targetted for the individual application

The shared assembly can be shared by the multiple application.

2) The private assembly has to be added for every application as reference
    The shared assembly has to be added into the GAC folder. All the application can be access the assembly.

3) The private assembly cannot have the versions. The name should be different.
    The shared assembly can have multiple versions and it will be identified by the strong name key.

The strong name key has to be assigned to the shared assembly. The sn.exe tool used to create the strong name key.
The gacutil.exe tool is used to install the shared assembly in GAC.
It will be stored into the  C:\Windows\Assembly OR C:\Winnt\Assembly folder

The shared assembly will have its own identity like strong name, version, etc..,


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