Assemblies in CLR

Assemblies are the building blocks of .NET framework applications. An assembly is a collection of similar types and resources that are build to work together and form a logical unit of functionality. Assembly provides the type implementation details for CLR. Assembly forms the fundamental part of deployment,version control,reuse,activation scoping and security permissions.

.NET binaries does not contain platform specific instructions. But instead it contains the paltform agnostic Intermediate Language (IL). It is also known as Microsoft Intermediate Language. All .NET aware compilers produces nearly identical CIL instructions.

JIT (Jitter) compiler compiles the CIL code into meaningful CPU instructions. JIT is flexible enough to execute in different tartgeted environments.

.NET Type Metadata : In addition to CIL instructions, .NET assembly contains metadata. It refers to each and every type, members of each type etc. Metadata is used by numerous aspects of .NET runtime environment.

Assembly Manifest: .NET Assembly also contains metadata that describes the assembly itself. This is called as Manifest. Manifest documents all external assemblies required by the current assembly, version number , copy right information etc.