Try one of these articles:
- Update Firefox to the latest version By default, Firefox is set to automatically update itself but you can always do a manual update. We'll show you how to update Firefox for Windows, Mac or Linux.
- How to download and install Firefox on Windows This article describes how to install Firefox on Windows.
- Install Firefox on Linux This article will show you how to install Firefox on Linux.
- Find what version of Firefox you are using This article shows you how to find what version of Firefox you have to help you troubleshoot a problem or just so you'll know if it's up to date.