The Mozilla Foundation, a group developing a family of open-source Internet applications, has two browsers. The Mozilla 1.7 Suite includes a browser, e-mail, HTML composer and publisher, IRC chat client, and Web development tools. Firefox (previously called Firebird) is the foundation's standalone browser, targeted at Internet Explorer users. Both are free, though donations are accepted.

For this review, we looked at Firefox beta version 0.9.2 (the final release should be available now). Unlike the other browsers we reviewed, Firefox installs just the essentials: a browser with a built-in pop-up blocker, a download manager, and a customizable search bar on the browser toolbar. The default search is Google, but you can add other search engines as well, and the list of available engines is impressive.

Your Internet Explorer defaults, bookmarks, and other settings are automatically imported, so you don't have to do or know anything. Once it's loaded, you won't have any trouble using the browser's unique features either.

Firefox's menu and selections mirror those of IE. Click Tools, then Options in Firefox, and you'll see a command set similar to IE's Tools and Internet Options. The difference: Every category is easier to configure and use.

Smart features abound in Firefox. For example, type "CNN" into the IE address bar and it thinks you're searching for that term. Do the same in Firefox, and it intelligently takes you directly to the CNN site, rather than a page of search results.

Tabbed browsing (found in every browser we reviewed) easily tracks multiple open windows. Instead of having to Alt-Tab through open windows, or mouse-clicking your way through the stack, Firefox allows you to easily switch between open pages just by clicking a tab at the top of the browser.

Another unique and aptly-named Firefox feature, called Find As You Type, easily finds keywords on Web pages. Just begin typing, and Firefox will quickly jump to the word, and even highlight it for you.

We also liked the ability to change Firefox's look and feel with software skins or adding new features, called extensions. Mozilla community members have created more than 100, and with them you can literally build your own browser.

Using the Extension Manager, we added an RSS reader to check our stock quotes, a utility that turns mouse gestures into browser command shortcuts, and a one-click button to clean our Internet history and cache. Other Extensions include a browser-based spell-checker and banner-ad blockers.

Extensions are an excellent feature, though many seem unfinished. This is not entirely surprising; as of press time, the browser itself was still in beta testing. The ability to build your own browser from the ground up, however, with an excellent foundation and numerous additions to choose from, makes Firefox our top pick.