It's probably a gross understatement to say that 2004 has been a tough year for Microsoft Internet Explorer.

The world's most widely-used Web browser has gotten hammered by repeated vulnerability disclosures throughout the year, and more and more hackers are trying to trick users into visiting malicious Web sites that can take advantage of IE in order to plant spyware and other malware onto PCs.

This security deluge has prompted some disgruntled users to abandon Internet Explorer for other browsers. Between June and July of 2004, IE market share slipped by over 1 percent from 95.48 to 94.16, according to a News.com report. It was the first time that IE has experienced such a downward trend since Web analytics company WebSideStory began tracking browser market share in 1999.

While alternative browsers such as Opera and Apple's Safari browser for Mac OS X now offer viable alternatives to Internet Explorer, the browser that is picking up most of the slack from IE is Mozilla, which increased its market share from 3.54 to 4.59 during the same period that IE lost its record number of users. Mozilla appears to be the biggest winner because of the growing popularity of its new upstart browser for Windows called Firefox.

Firefox, a newly-engineered Web browser that uses Mozilla's Gecko engine, differs from the actual Mozilla product (and its Netscape legacy) in that it is only a browser and does not contain all of the additional built-in applications such as a mail client, a newsreader, and a chat client that come with the Mozilla suite. As a result, Firefox is leaner and faster and has less of an imprint on RAM utilisation.

However, the value proposition of Firefox isn't simply a "less is more" move. It has a different interface than Mozilla and includes unique features such as popup blocking, an integrated Google search toolbar, and tabbed browsing (a way to open different windows as tabs, similar to the way different spreadsheets are on different tabs in Microsoft Excel).

While all of those features are appealing, the reason Firefox is winning converts is because of its security. Mozilla developers have built this browser with security and privacy as top priorities. Firefox does not load Active X controls, it does not support VBScript, and it is not integrated directly into Windows, so even if a hacker exploited the browser, the system itself couldn't be compromised quite as easily.

Next to its security, the best thing about Firefox is probably the fact that it renders most Web sites clearly and effectivelyââ,¬"in most cases, it does a better job than Opera and Mozilla in this regard. That helps to ease the pain for someone migrating from IE to Firefox as the primary Web browser. For an administrator making that switch for the users on a network, the following is a short list of things to like and dislike about using Firefox in a corporate environment.

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