Mozilla Firefox, informally known as Firefox in Chinese, is an open source web browser, which uses Gecko engine (that is, non-ie kernel) and is jointly developed by Mozilla Foundation and hundreds of volunteers. Originally known as "Phoenix", it was later renamed as "Mozilla Firebird" and later changed to its current name.

Mozilla Foundation is located in Mountain View, California, USA. The Mozilla Foundation describes itself as "a non-profit organization dedicated to providing diversified choices and innovations in the Internet field".