Why use strong named assemblies?

Let me list the benefits of strong naming your assembly first:

1. Strong naming your assembly allows you to include your assembly into the Global Assembly Cache (GAC). Thus it allows you to share it among multiple applications.

2. Strong naming guarantees a unique name for that assembly. Thus no one else can use the same assembly name.

3. Strong name protect the version lineage of an assembly. A strong name can ensure that no one is able to produce a subsequent version of your assembly. Application users are ensured that a version of the assembly they are loading come from the same publisher that created the version the application was built with.

More on strong naming from Microsoft is in Strong-Named Assemblies (MSDN).