What is ASP?
ASP stands for Active Server Pages, and it's free! It's built into Windows 2000, and can easily be installed on Windows 95/98/NT.
Maintainance of an ASP site is much simpler because of SSI (Server-Side Includes). This allows me to have a Header() function in one file that every page on the site includes. If I want to change the page header I just change that one file - try that with HTML!
As far as you or your browser is concerned it's a plain-jane HTML page. View the source HTML for this page and you'll see another advantage - although I'm looking at perfectly formatted and easy to read code, all you see is virtually unintelligible HTML with no spaces or comments.
This dramatically speeds up my pages too since I'm sending less data to your browser. When converting the site from FrontPage to ASP I saw some pages shrink from 40kb to 3kb, which translates to a speed improvement on a typical modem from 12 seconds to less than 1!