Actually, its a tricky question that which a interviewer asked.We cant able to compare both of them. We should mention the definition for it and give simple examples..
Everything in a a .NET framework is treated as objects. The logical collection of these related is known as NameSpace.
eg: to implement these data objects to a project, we use NameSpaces like:
Assembly is a small file that create in the first successful run of a asp.net application. It contains the MSIL and Metadata. It helps in the smooth running of the application.
There are two types of assemblies: private and shared. A private assembly can be used by only a single application. A shared assembly, on the other hand, can be used by all applications located on the same server
eg. of an assembly is