Server Side Languages can be used to develop applications/scripts that are executed ServerSide on a web-server before a client downloads it.
Many languages can be used to develop ServerSide web applications by using CGI ( CommonGatewayInterface ) but some languages can be used to integrate an application more closely with a web-server application or provide better funcionality for developing webpages. These languages include,
SchemeLanguage (see SUnet (specifically, the version in CVS with 'surflets') and the PLT web server)
HaskellLanguage (see WASH)
SmalltalkLanguage (see Seaside)
