The following is from the: Techencyclopedia Web site / techweb.com
ASP:
(Active Server Page) A Web server technology from Microsoft that allows for the creation of dynamic, interactive sessions with the user. An ASP is a Web page that contains HTML and embedded programming code written in VBScript or Jscript. It was introduced with Version 3.0 of Microsoft's Internet Information Server (IIS). When IIS encounters an ASP page requested by the browser, it executes the embedded program.
ASPs are Microsoft's alternative to CGI scripts and JavaServer Pages (JSPs), which allow Web pages to interact with databases and other programs. Third party products add ASP capability to non-Microsoft Web servers. The Active Server Page technology is an ISAPI program and ASP documents use an .ASP extension. ASP.NET is an enhanced version of ASP for the .NET platform.
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ASP allows for Web page dynamics, being able to use software applications on the server allows the Web developer to allow the client to harness the power of word processing, database, spread sheet and other powerful applications. This can increase the meaningfulness and productivity of a users Web experience and is the foundation of e-commerce.
Static Web pages are still used and highly trafficked but the ability to create or "generate" Web pages on the fly that incorporate text, images, user data, database data, spread sheet data and other forms of content output has become the standard by which Web sites/pages are measured.