ASP stands for Active Server Pages. ASP are text files that can contain both server-side scripting and client-side scripting. The server-side runs under Internet Information Server (IIS). Frequently, the purpose of the server-side code is to build hypertext markup language (HTML) tags that will be sent to browser. Any client-side scripting in the ASP are then executed by the browser. This client-side scripting is often done with JavaScript, but it can also be done with VBScript.