Firefox is a desktop browser.
Mozilla Firefox ( or simply Firefox ) is a free and open-source web browser developed by the Mozilla Foundation and its subsidiary the Mozilla Corporation . , Firefox has between 9 % and 16 % of worldwide usage as a `` desktop '' browser , making it the second most popular web browser . Firefox is still the most popular desktop browser in Cuba ( even most popular overall ) , Eritrea , and Germany , with 85.93 % , 79.39 % , and 37.01 % of the market share , respectively . It is also the most popular desktop browser in many other African countries .