SQL : Structured Query Language .<br><br>It is a language that provides an interface to relational database systems.<br><br>SQL was developed by IBM in the 1970s for use in System R.<br><br>SQL is a de facto standard, as well as an ISO and ANSI standard..<br><br>It is a special-purpose, nonprocedural language that supports the definition, manipulation, and control of data in relational database management systems.