A Netscape extension that allows you to divide your browser window into different, independent sections called frames, each scrollable and assigned their own separate URL. The advantage of frames is it allows the user to navigate a web site in one frame while another frame stays stationary. The static frame usually contains a navigation bar or banner ad. Frames aren't official HTML, but are supported by many browsers including Netscape Navigator and Microsoft's Internet Explorer. Creative use of frames can make for some interesting sites. However, there's a strong and vocal anti-frame populace online, people who feel the benefits of frames aren't worth the hassle: Older browsers can't do a thing with frames, so you have to either build a separate site for people using these browsers or force people to upgrade. Also, because the URL stays the same as you navigate a framed site, bookmarking individual pages can be tricky, so users charmed by an individual page on your site may have some trouble getting back to it. Before you build your next site, start by asking yourself whether it's really worth framing.