Firefox (referred to as Fx) is an open source browser developed by Mozilla. The second most popular browser worldwide, Firefox features a customizable user interface that allows you to enhance it using custom themes and Personas. Personas change the appearance of the user interface without rearranging the elements. Themes however, can completely change the UI ranging from the types of buttons to the color sceme used. Add-ons allow you to customize Firefox to your liking to make a more enjoyable web surfing experience. Some examples of popular add-ons that you can use to customize Firefox are AdBlock Plus, DownThemAll!, TabMixPlus and many more.
Firefox has tabbed browsing, bookmarks, a built in session manager, private browsing, personas, themes, add-ons and more. Firefox does not use ActiveX which helps make it a more secure browser. Firefox does make use of many plugins to enhance your web experience. From Shockwave, Flash, Quicktime and more; your browsing experience reaches new levels with the Firefox browser.