A relational database management system (RDBMS), the SQL server was designed for client/server use and is accessed by applications using SQL. It runs on OS/2, Windows NT, NetWare servers, VAXen, and Unixworkstations. Generically, it is any database management system (DBMS) that can respond to queries from client machines formatted in the SQL language. The term refers to either of two database management products from Sybase and Microsoft. Both companies offer client/server DBMS products called SQL Server.