Active Server Pages (ASP), also known as Classic ASP or ASP Classic, was Microsoft's first server-side script-engine for dynamically-generated web pages. Initially released as an add-on to Internet Information Services (IIS) via the Windows NT 4.0 Option Pack (ca 1998), it was subsequently included as a free component of Windows Server (since the initial release of Windows 2000 Server). ASP.NET has superseded ASP.
ASP 2.0 provided six built-in objects: Application, ASPError, Request, Response, Server, and Session. Session, for example, represents a cookie-based session that maintains the state of variables from page to page. The Active Scripting engine's support of the Component Object Model (COM) enables ASP websites to access functionality in compiled libraries such as DLLs.