LINQ stands for language-integrated query with that query becomes an integrated feature of the developer's primary programming languages (for example, Visual C#, Visual Basic).
Language-integrated query allows query expressions to benefit from the rich metadata, compile-time syntax checking, static typing and IntelliSense that was previously available only to imperative code. Language-integrated query also allows a single general purpose declarative query facility to be applied to all in-memory information, not just information from external sources.