LINQ stands for Language-Integrated Query, which means that data retrieval is no longer a separate language. The LINQ engine allows .NET applications to connect to databases without bothering much about columns and rows. The data you receive is automatically formed as objects ready to use by your business logic.

LINQ to Relational Data may be thought of as an object-relational mapping (ORM) tool. The type-safe LINQ queries get compiled into MSIL on the fly, and the query clauses are translated into SQL and sent to SQL server for execution. This makes your data access layer safer, faster, and greatly more convenient to design.