An assembly in the .NET Framework contains the following four elements:

• Assembly manifest
• Metadata
• MSIL code
• Resources

These elements can be grouped into one assembly, as shown in the following screenshot. Here, the runtime requires manifest information in order to get the type information, the dependent assembly information, the version, and the unique name of the assembly in order to execute:

The .NET Framework also allows us to group the four elements of the assemblies into multiple modules and create an assembly to refer them while executing the program block. When you refer such modules in an assembly, it is the manifest file that maintains all the links required to refer to these resources:

An assembly manifest contains the name of the assembly, the version of the assembly, which culture is used to build the assembly, the strong name information (that is, public key), the type information, a list of files and how they are associated with each other and the assembly, and, finally, a list of referenced assemblies and their versions. We can add more information by updating the AssemblyInfo.cs file.

A manifest file can be part of the portable executable (PE) file along with MSIL or a standalone PE file. Each assembly file contains all the files that are required for an assembly; it governs how the mapping between these files, resources, and assemblies are maintained, and it also contains referenced assemblies.