At one point there were only two web browsers in the world, one was Mosaic (Mozilla is short for Mosaic Killer) and one was W3 (the emacs web browser).
I don't think Mosaic was the original browser and I believe others predated Emacs, such as Lynx. Here's Wikipedia's version of events, for what it's worth:
At one point there were only two web browsers in the world, one was Mosaic (Mozilla is short for Mosaic Killer) and one was W3 (the emacs web browser).