By Preston Gralla
December 10, 2008

Firefox 3.1 may only be a point release -- from 3.0 to 3.1 -- but its just-released Beta 2 version is a good indication that the final release will be a must-have upgrade for anyone using Firefox. Beta 2 (now available from Mozilla) unveils the browser's most important new feature -- Private Browsing, which automatically deletes all traces of a browsing session.

In addition, the new beta turns on a feature designed to make the browser up to 40 times faster (at least, according to Mozilla). Browsing in private - The most important new feature in Beta 2 is the addition of Private Browsing -- the same feature that is called Incognito Mode in Chrome and InPrivate Browsing in Internet Explorer 8.

All traces of your browsing session are deleted when you use Private Browsing -- your browsing history, temporary Internet files, search history, download history, Web form history and cookies. (For obvious reasons, it's popularly known as "porn mode.") To launch a Private Browsing session, choose Tools --> Private Browsing. When you do that, you'll get a warning that Firefox is going to close all of your current tabs to launch a Private Browsing session.

Select Start Private Browsing, and from then on, the history of your session won't be kept. The only indication that you're using Private Browsing are the words Private Browsing in the title bar of your browser. To exit Private Browsing and return to your normal session, select Tools and uncheck the mark next to Private Browsing.