A type library is a standard format for interface descriptions. It can store interface or class meta-data and make them accessible for different clients. Type libraries enable clients to call interfaces without knowing their actual implementation.
Type libraries are widely used in com environments to describe interfaces, classes or type definitions. They are created to export interface contracts to clients. This way, they define a standardized interface between servers and clients.
In COM, type libraries can be described using idl (interface definition language).
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