NOTE: Much of this was content written ten years ago, so it may be a little archaic now.
Mozilla Firefox is a piece of software derived from the original Netscape web browser. There are many good reasons to try out Mozilla Firefox if you haven't done so already, or choose to use it as your everyday web browser.
Below follows an overview of some advantages and compelling features Mozilla Firefox 1.0.x has in relation to its competition. Firefox 1.5 and 2.0 brought about even more features, and most of these points carry over to the Mozilla application suite and SeaMonkey as well.
Mozilla Firefox has always contained a versatile and built-in pop-up window blocker that prevents sites from initiating unrequested windows. An icon appears on the status bar when a pop-up window would otherwise appear, and it is also easy to exempt sites from this feature if you wish to receive a pop-up window.
In addition, Firefox has the capability of not accepting images from specified servers, which can be used to avoid seeing undesirable advertisements or pornography. Firefox also offers similarly powerful ways to manage cookies.
There's no need to clutter your desktop or taskbar and bog down your resources with multiple instances of your browser when you wish to simultaneously load several pages. Tabbed browsing (first implemented in the Mozilla application suite in late 2001) allows you to load as many pages as you like in the same browser window, and increases productivity by giving the capability of viewing one page while waiting for another to load. Switching between pages is as easy as a click away. You can even load pages in new tabs by dragging and dropping links into the tab bar or either Ctrl+clicking or middle-clicking on a link. Another handy key combination is Ctrl+Tab, which switches between individual tabs. Firefox 1.5 adds the capability of reordering individual tabs loaded on the tab bar through dragging and dropping.
Mozilla Firefox has a built-in update feature that periodically checks that your browser--and even third-party themes or extensions you may have installed--are up to date.
Mozilla Firefox 1.0.x used a special button (at right) to indicate the presence of available updates. The button was color-coded to indicate the following:
(Thanks to Tim Wolfe for providing this information!)
In Mozilla Firefox 1.5, the update system was thoroughly revised. The new system is more automated, downloads small incremental updates rather than an entire package when a newer version is available, and can run either automatically or through an option in the Help menu.
Live Bookmarks are an innovative feature present in Mozilla Firefox (1.0 PR and later) that allow you to view RSS feeds from any of hundreds of websites directly in your Bookmarks menu or Bookmarks Toolbar. This technology allows you to view the latest, automatically updated headlines from your favorite websites at a glance without even having to know what RSS is. When a site offers an appropriate RSS feed, an icon appears on the Firefox location field (1.5+) or status bar (earlier versions); clicking on it allows you to easily position a Live Bookmark in your Bookmarks. It is even possible to use services to publish your own bookmarks as Live Bookmarks for others to use.
More information on Live Bookmarks.
You can test your current browser's security at this website.
Mozilla Firefox has built-in searching capability that can be tied to a variety of search engines, several of which are provided by default and more of which can be added as options. A convenient Search bar (right) is built into the toolbar. You can find information by highlighting words or phrases, right-clicking, and choosing the "Search Web for..." option or even by dragging words or phrases to the "Search" bar.
Unlike Microsoft Internet Explorer or (for that matter) Netscape per sé which stagnate for years on end between major releases, Mozilla Firefox is substantially updated at least once a year. Each new release offers a selection of new features and bug fixes which enrich the product. "Profiles" containing information such as bookmarks are saved in a different folder, and are not affected by uninstalling a version of the software. It has been safe to install a newer version of Mozilla Firefox directly over an older one since version 1.0, and a built-in update system has been implemented in recent versions of Firefox and Thunderbird, further simplifying the process.
Mozilla Firefox is a technologically sophisticated browser with support for the latest rendering technologies. Embracing the full potential of Cascading Style Sheets technology, its "Gecko" rendering engine offers includes comprehensive CSS1 and generous CSS2 support, and is the best in the industry at conforming to these standards which are set by the World Wide Web Consortum. In addition, Firefox follows the guidelines of published web standards closely and accurately and also fully supports transparent PNG images, unlike Netscape Communicator 4.x or Internet Explorer 6.0.
Mozilla Firefox can be extensively customized. It has the built-in capability for themes, which can dramatically change the look and feel of the software without cutting any functionality. In addition to the default theme (which utilizes some OS-native controls), a growing number of third-party themes can be obtained from various websites. Extensions and modifications such as the popular Adblock accessory can be installed, and a service called "Add-ons" has been created to keep users informed of themes and extensions and keep them up-to-date. In addition, advanced users can easily edit a list of technical settings by typing "about:config" in the location field. Mozilla Firefox's toolbars are extensively customizable.
One of the most important assets of Mozilla Firefox is its cross-platform availability. Versions of Mozilla Firefox are officially released for Windows, Linux, and the Apple Macintosh, and releases have also been contributed for other operating systems such as IBM OS/2 and UNIX variations such as Solaris, AIX, and HP-UX. Each release is virtually equivalent in essential features and rendering capability regardless of platform, allowing webmasters and computer support technicians to rest assured that Firefox users enjoy a similar web experience no matter what platform they use. By comparison, Microsoft Internet Explorer 6.0 has been released for only one operating system, Windows, and future versions will not run on Windows 95, 98, ME, NT, or 2000.