(note the correct capitalization) is the current name of Mozilla's
browser-only package, formerly known as "Firebird" and "Phoenix". Mozilla's Gekko web browsing engine
(what Firefox is based off of) is being implemented into SL
and, so far, is used in its help menu.
Firefox is the best web browser there is. You should be using it to read the LSL Wiki.
Get it at http://www.mozilla.org/products/firefox/