Since its release in 2004, Firefox started to gain popularity at a fast pace, currently being the most popular web browser on Linux. It's well known for its security, and there are hundreds of add-ons and themes available for it, transforming it into a very useful tool, not only a simple browser.
Built using GTK, Firefox has a clean interface, yet allowing the user to easily configure the most important aspects via the Preferences window. It includes a download manager, customizable tabs, RSS feed reader, an easy way to manage cookies, private data and passwords (one of its great features is the ability to remember passwords - even when you change them, Firefox successfully detects the login information most of the time). Firefox can also detect untrusted sites, which are suspected to be a threat to the user's security, by checking with a specified list of such websites.
Another strong point for Firefox are the add-ons, which practically provide anything you can think of. The StumbleUpon toolbar, DownloadHelper (used to download videos, including the ones from YouTube), UbuntuForums menu, are just a few of the many add-ons available to Firefox.
Using the Noia eXtreme theme (click to enlarge)
There are plenty community-made themes too, which can change the look of this browser drastically. Some examples are futuristic themes, eye-candy themes or computer themes.
The only negative aspect I could find about Firefox is that it's very resource hungry: it eats both CPU and RAM. It's well-known for being pretty slow, at least when it is started for the first time, but well, that comes with the territory.
Preferences (click to enlarge)
It uses the Gecko engine for rendering pages and the nice aspect is that Firefox properly displays web pages where other browsers fail to do so.
It's well documented: it explains every aspect on how to use it in a simple fashion, so even a newcomer will find the help useful. Version 18.104.22.168 is the latest stable release, but 3.0 is due to be out very soon, 3.0RC3 being the latest release candidate.
As a conclusion, I think Firefox is one of the great pieces of software open-source gave in the last years.
Official Firefox Website
Opera is the only closed-source graphical user interface browser that I ever used on Linux. This version was recently released, and brought in some great improvements, like a new user interface, the quick find ability (which searches in the content of visited pages), and very fast load times. The latter is also Opera's strong point in my opinion: it's pure and simple extremely fast. And navigating web pages seems smoother than it is when using other browsers. Among many features, Opera comes with an integrated BitTorrent client, a Speed Dial page (for previewing up to 9 web pages in a single tab), integration in the system tray (this is a useful feature which Opera has for a long time), widgets. Those are just a few though.
Opera 9.50 - Dozens of improvements, new interface
I like very much Opera's approach to use tabs for almost everything: the About page is displayed as a tab, transfers are opened in a new tab and the same goes for history. It's practical and easier than having a separate window for each task. Not to mention that it's highly configurable, without looking bloated. Opera was built using the Qt 3.3 kit.
Opera Preferences window
Except for the fonts which were too small and I had to adjust them after I first started Opera, everything is great about this browser. Well, not everything: it's still closed-source. But beyond that, this is an extremely good and complete browser, which really shows that intensive work has been put into it.
Official Opera Website
Using the KHTML engine, Konqueror is the default browser in KDE. Of course, it's also a powerful file manager, image or PDF viewer, but in this review I'll only look at its browsing capabilities. Although it sometimes fails to submit certain forms or display correctly certain web pages (probably the ones using a newer HTML version), Konqueror will offer a good browsing experience if you are a KDE user.
Konqueror on KDE 3.5.9
One of the features is the integration with KGet, which is a pretty complex download manager for KDE, benefiting of the possibility to be embedded in the system tray. Using it both as a browser and file manager can also be an advantage, considering you can have a web page opened in a tab and browse the filesystem at the same time, in another tab.
It's probably the most configurable one from these three browsers. A nice feature which proved to be very useful is constituted by the web shortcuts: you only type a shortcut in the address bar and Firefox will open the respective search engine with the keyword you specified. For example: you can search on Wikipedia for Pink Floyd just by typing wp:pink floyd in Konqueror's address bar. Or you can search on Google for KDE news by typing gg:kde news. Very useful and fast. The thing is, once you get used to this feature, you'll miss it in other browsers. Of course, you can add your own custom search engines, if the default list (which contains maybe 100 such websites) is not enough.
One of the good features: web shortcuts
It's the browser which loads the fastest of all three, and it's also the most light, but unfortunately it looked to me like the one taking the longest amount of time for loading and displaying a web page completely.
Websites often report Konqueror is unsupported, but that is not a problem if you switch the user agent in the Settings -> Configure Konqueror -> Browser Identification tab to Mozilla. You can set the user agent only for specific websites, or for general use.
Easily change the version Konqueror will report to specific websites
Overall, Konqueror is a very good browser whose only minus is failure to submit certain forms or correctly display certain pages. They are a few, but even though, it can get a little annoying. I recommend Konqueror to those who use KDE. It really offers good advantages this way.
Official Konqueror Website
Updated: Jun 15, 2008 (Created: Jun 15, 2008)