Programming ASP websites is made easier by various built-in objects. Each object corresponds to a group of frequently-used functionality useful for creating dynamic web pages. In ASP 2.0 there are six such built-in objects: Application, ASPError, Request, Response, Server, and Session. Session, for example, is a cookie-based session object that maintains variables from page to page. Application Center Test is also available for load testing.

Most ASP pages are written in VBScript, but any other Active Scripting engine can be selected instead by using the @Language directive or the <script language="language" runat="server"> syntax. JScript (Microsoft's implementation of ECMAScript) is the other language that is usually available. PerlScript (a derivative of Perl) and others are available as third-party installable Active Scripting engines.

"PWS is a smaller, but fully functional version of IIS. To run PWS, we need Windows 95 or later. InstantASP, ChiliASP are technologies that run ASP without Windows Operating System."

There are large open source communities on the WWW, such as ASPNuke, which are producing ASP scripts, components and applications to be used for free under certain licence terms.

Versions
ASP has gone through six major releases:

ASP version 1.0 (distributed with IIS 3.0) in December 1996,
ASP version 2.0 (distributed with IIS 4.0) in September 1997,
ASP version 3.0 (distributed with IIS 5.0) in November 2000,
ASP.NET version 1.0 (part of the Microsoft .NET platform) in January 2002
(the pre-.NET versions are currently referred to as "classic" ASP)
ASP.NET version 1.1 in April 2003
ASP.NET version 2.0 (released on November 7, 2005).
ASP.NET was originally called "ASP+" or "ASP PLUS" before the .NET name was introduced.

The move from ASP 2.0 to ASP 3.0 was a relatively modest one. Some of the most important additions were the Server.Transfer and the Server.Execute methods, as well as the ASPError object.[1] Microsoft's What's New in IIS 5.0 lists some additional changes.

The move from ASP 3.0 to ASP.NET was a significant change. ASP.NET introduced the ability to replace in-HTML scripting with full-fledged support for .NET languages such as Visual Basic .NET and C#. In-page scripting can still be used (and is fully supported), but now pages can use VB.NET and C# classes to generate pages instead of code in HTML pages.

There are solutions to run "Classic ASP" sites as standalone applications. One of them is ASPexplore - a software package that runs Microsoft Active Server Pages off-line, without any web server. ASPexplore provides solutions to create fully fledged ASP-based Windows applications and their setups.