Language Interoperability
The CTS plays an integral role in allowing language interoperability because it defines the set types that a .NET compiler must support in order to interoperate with other languages. The CTS itself is defined in the Common Language Specification (CLS). The CLS defines a single set of rules for every .NET compiler, ensuring that each compiler will output code that interacts with the CLR consistently. One of the CLS requirements is that the compiler must support certain types defined in the CTS. The benefit being that because all .NET languages are using a single type system, you are assured that objects and types created in different languages can interact with one another in a seamless manner. It's this CTS/CLS combination that helps make language interoperability more than just a programmer's dream.