One of the safest, most efficient and bullshitless browsers out there (among others such as Opera).
Has the most useful plugins ever created, such as "FlashBlock" which completely eradicates flash ads on web pages that may slow down your browsing, and those annoying "Shoot the Ninja and get a free iPod!" ads. As well as Fasterfox, which optimizes the speed, and many more.
The great thing about this browser is that it DOESNT install crap on your computer without asking you prior to that...Internet Explorer by Microsoft, for example, randomly changes it's homepage, installs adware and spyware and third party crap without your knowing.
With a built in google toolbar (which, incidentally, doesnt take up 3/5ths of the screen like on IE), it makes searching a breeze.
Definitely the way to go for an optimized browsing experience.
-dude, internet explorer blows
-fsho get firefox
Prices shown in USD.