Microsoft's Active Server Pages (ASP) is server-side scripting that you can use to create and run dynamic, interactive Web server applications. With ASP, you can combine HTML pages, scriptlets, and COM components to create interactive Web pages or Web-based applications.

With ASP, you can collect information from web forms and pass it to a database scripts embedded directly in your HTML documents. If you are already familiar with scripting languages such as Microsoft VBScript you will have little trouble learning ASP.

Besides adding scripts to create the presentation layer (user interface) for your application, you can build your own COM (common object module) components. You can encapsulate your application's business logic into reusable modules that you can call from a script, from another component, or from another program. This enables the separation of business logic from the presentation layer.

A server-side script begins to run when a browser requests an .asp file from your Web server. Your Web server then calls ASP, which processes the requested file from top to bottom, executes any script commands, and sends a Web page to the browser.

Unlike JSP which is supported by several web 'application' servers, ASP is largely Microsoft only, but integrates seamlessly with IIS (Internet Information Server).

Because your scripts run on the server rather than on the client, your Web server does all the work involved in generating the HTML pages sent to browsers. Server-side scripts cannot be readily copied because only the result of the script is returned to the browser. Users cannot view the script

Because it uses ActiveX controls for its components, ASP technology is basically restricted to Microsoft Windows-based platforms. Offered primarily as a feature of Microsoft IIS, ASP technology does not work easily on a broader range of Web servers because ActiveX objects are platform specific.

This is in contrast to Java and Java Server Pages.