A FireFox download can be a number of different things. If you have never used FireFox, and you are downloading it for the first time, this would be the act of downloading it off the internet for free. However, if you are already using FireFox, downloading the latest version would be an update of some kind. That is the great thing about using FireFox. Not only is it free, it will keep itself up to date with all the different FireFox Downloads out there.
The best thing about the FireFox download is that it will look for these downloads automatically. There is no need for you to go out looking for them, because as soon as there is a new download for your FireFox web browsers you will be told. Then it will ask if it's fine to go ahead and install your update. Keeping your internet browser up to date is very important work, and with FireFox download updates, this task just got a lot easier.