is used to build and manipulate relational databases. It is a declarative, rather than a procedural, programming language. In a declarative language, statements express/describe/declare what is to be done, rather than provide the specifics of how something is to be done as is the case in procedural languages. Internally, database systems translate SQL to relational algebra. There is a standard for SQL, but database vendors vary in how closely they implement it. This website emphasises the standard and thus examples presented can be executed on all relational database systems with some minor (if necessary at all) changes.