Keywords in different version of SQL Server

Keywords in SQL Server 2000: http://msdn.microsoft.com/en-us/library/aa238507.aspx

Keywords in SQL Server 2005: http://msdn.microsoft.com/en-us/library/ms189822(SQL.90).aspx

(Added: EXTERNAL, SECURITYAUDIT, PIVOT and UNPIVOT, REVERT)

Keywords in SQL Server 2008: http://msdn.microsoft.com/en-us/library/ms189822.aspx

(Added: MERGE)

Newer versions actually have fewer keywords.