It was developed by Microsoft to allow programmers to build dynamic web sites, applications and services. It was first released in January 2002 with version 1.0 of the . NET Framework and is the successor to Microsoft's Active Server Pages (ASP) technology.

When you type in a URL in the Address Box of your browser, you are asking the web server to send the file to your computer. If the file is standard HTML, then the file that your web browser receives will look exactly the same as it did on the web server. However, if an ASP file is sent to your computer from the server, it first runs the HTML code, then the ASP code. The ASP code could be anything such as the current time, date, or other such information.