Firefox is the long-time competitor to IE that staved off a Microsoft browser monopoly for years until Chrome showed up to “help.” It’s fast and very reliable. Despite a longstanding memory leak that forced the occasional restart, it was the browser I recommended for many users to avoid the malware attacks that once plagued IE.
The memory leak in its Gecko rendering engine seems to be gone and Firefox has recently received an upgrade that was radical enough to rile a few longtime users.(There is a way to bring back the old-style menus.)
I prefer the new look and find it the most intuitive of all the browsers for bookmarking and changing options. Firefox also has a vast array of add-ons, including one of the best video downloaders out there, the aptly-named DownloadHelper.