Does the DLLs of the Class Projects gets updated in the Web Project when we compile the solution?

Hello,
I have a solution which has 2 class Library projects and one web project.
In the BIN folder of my Web Project I have included the dll's from both my class libraries. ( ClassLib1.dll and ClassLib2.dll).
My Question is when I make changes to ClassLib1 project, lets say if I add a DLL to the BIN folder of my ClassLib1 project and when I compile the sopution. Does the ClassLib1.DLL in my Web project will get updated?
Also when I have to deploy the project on the web server. Do I need all the ClassLib Projects? Becuase what I am thinking is that I already have the DLL's of my classProjects in my Web Projects then there should not be any need of the actual ClassProjects on the web server?
If someone can throw some light? Thanks.















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