Ubuntu regularly claims to be the most popular Linux distribution. But, if so, Fedora is a competitive second. Both have thriving communities and are a major source of free and open source software innovation.
Regularly, you can read on mailing lists of users having grown discontented with one and deciding to migrate to the other. In many users' minds, each is an alternative to the other.
But how do the distributions really compare?
The most reliable answer is to examine the latest releases, Ubuntu 10.04 (Lucid Lynx) and Fedora 13 (Goddard) -- or, to be exact, Fedora 13's release candidate, since last minute concerns delayed the final release that was expected this week by another seven days. Dealing with a release candidate does put some restrictions on the comparison, but, to judge from previous releases, not enough to affect the overall impressions.
Basically, with its reputation for innovation and its determination to provide only free software, the latest Fedora ranks among the best of the traditional distributions, with a GNOME desktop only lightly customize and branded. By contrast, Ubuntu's latest version places a higher emphasis on usability and commercial competitiveness -- so much so that it is making many of its changes inside the distribution before they are accepted by the GNOME project itself.
Yet despite these different outlooks and goals, the differences turn out to be small, especially from an end-user's perspective.
Installation and Bootup
Most of the reservations about working with the Fedora release candidate are about installation and starting the new system. To start with, the Fedora team has chosen not to focus on squeezing a usable system on to a single CD during development, leaving most users to download a CD set or a single DVD. The sole exception is the KDE spin, which does have a Live CD. While the Fedora download page promise s Live CDs for the final release, for now, the curious are left with a three hour download (unless you get lucky with BitTorrent). This decision is much less convenient than the single CD for the latest Ubuntu download.
Both Ubuntu and Fedora have simple default installs, aimed more at newer users than experts, although Ubuntu also offers a more customizable alternate installer. Each of the defaults creates a single ext4 installation partition and a swap partition, although Fedora's default swap partition is almost a quarter larger than Ubuntu's.
To boot, Ubuntu uses GRUB2 -- the only major distribution, so far as I know, to do so. Like most distributions, Fedora continues to use GRUB Legacy, a difference that newer users will never notice and more experienced users might prefer because it is easier to edit manually.
Both distributions use Plymouth to reduce bootup time, although in practice, the Fedora release candidate took almost ninety seconds to boot on my test machine, compared to nineteen seconds for Ubuntu. Judging by the previous official releases, this difference is likely to narrow considerably after Fedora 13's official release, but not be eliminated entirely.
GNOME with a difference
Both Fedora and Ubuntu are GNOME-centered distributions, with KDE, Xfce, and other desktops as alternatives. Fedora has included fresh art for each new release for several years now, so its wallpaper compares favorably with Ubuntu's much-discussed new color-coded scheme.
In fact, apart from the fact that Fedora's desktop wallpaper favors shades of blue while Ubuntu's is mostly shades of aubergine (purple), the two themes are remarkably similar, each one involving semi-abstract gradients and swirls of color. You might not think that the same artist had done both wallpapers, but they could easily be from the same school of design.
The two desktops are also easily recognized as variations on standard GNOME, with one panel at the top for menus, applets, and other basic utilities such as the notification tray and date and time, and another on the bottom for a task bar and virtual work space.
Both use the standard GNOME trio of Applications, Places, and System for menus, with a limited selection of available applications and only minor variations in the arrangement of items -- for example, Ubuntu places a virtual terminal under Accessories while Fedora uses System Tools. However, in general, the differences in the desktop are minor. Admittedly, Ubuntu has simplified the GNOME menus slightly more than Fedora has, but this is an ambiguous advantage at best, especially since the simplification does not extend beyond the top level in the menus. Drill down, and part of the time you're going to encounter a few long sub-menus.
Still, the departures from standard GNOME that do exist are largely in Ubuntu. Working within the distribution rather than within the GNOME project, Ubuntu has rewritten the notification system, making it more useful, but also more obtrusive.
Ubuntu has also given the corners of the desktop specific functions: the top left for menus, the top right for log off actions, the bottom left for showing the desktop, and the bottom right for the trash can. Another Ubuntu innovation is the MeMenu, which attempts to create a centralized place for managing social media accounts and chats.
Undoubtedly, the largest difference in Ubuntu defaults is the placement of the title bar buttons on the left and the elimination of the window menu. This arrangement leaves a broad space on the right of each window's title bar, which in another release or two might be filled with some other useful information.
Yet for all the discussion of this arrangement, the worst that can be said is that it is initially awkward, while the best is that you can quickly get used to the change. Despite all the attention lavished on the change, it really doesn't affect your computing for better or worse.
Productivity Software Selection
Neither the latest Fedora nor Ubuntu strays very far from their shared GNOME roots in software selection. Both include the standard GNOME productivity applications, such as Firefox for browsing, Evolution for Email, and Empathy for messaging.
Each distro does include some applications that the other doesn't. For example, Ubuntu includes Computer Janitor and Gwibber, while Fedora boasts Network Manager and its ABRT (Automatic Bug Reporting Tool). Yet, generally, the differences are not vast.
The greatest difference is that, because Fedora uses Shotwell for image management and Gnote instead of Tomboy for a note system, it does not depend on the controversial Mono framework. These decisions seem to have been made to help free space on the Live CD, but those who disapprove of Mono will probably welcome them.
If anything, the most important difference in the distros' selection of productivity software is that Fedora includes only free software. If its users want to use Adobe Flash or Adobe Acrobat, they have to look elsewhere, and not in the Fedora repositories. The same goes for proprietary NVidia drivers and the MP3 codec.
Ubuntu, though, focusing on ease of use, has a looser policy, warning users of the disadvantages of proprietary software, but including it in repositories if the free software alternatives are weak or non-existent. Its Hardware Drivers tool in the Administration menu is essentially designed for managing such proprietary exceptions.
Yet, in the name of usability, Ubuntu does provide a link to the libdvdcss2 library for viewing videos. Although, like Fedora, it declines to include the library in its repositories because of its uncertain legal status in many parts of the world.
The selection of administration tools is also similar in the two distributions. However, at first you might think that Fedora has fewer because they are divided between the Application -> System Tools and System -> Administration menus.
Even when the distributions include different applications for the same function, you frequently need to be watching closely to see the difference. The most obvious example of this similarity is Fedora's PackageKit and the Ubuntu Software Center, the tools used for the installation of software packages.
Although developed separately and arranged differently in their windows, the functionality is almost identical, so much so that a casual user is unlikely to guess that Fedora uses .RPM packages and Ubuntu .DEB packages. Although PackageKit has more options for filtering the results that are displayed, the most visible difference is the larger size of the Ubuntu Software Center's icons, which makes the package installer superficially more user-friendly.
For the security conscious, Fedora has an edge because of its use of SELinux, which is more comprehensible and more customizable than Ubuntu's AppArmor. Yet this advantage is subjective, given that SELinux is more complex and harder to use. Someone wishing to learn more about security, or to turn it off, might well prefer Ubuntu's AppArmor.
Down to the wire
The default choices in the latest Ubuntu and Fedora releases are both based on a version of the GNOME desktop that represents eight years of constant evolution. Each distribution modifies the desktop, but rarely to an extent that the other cannot duplicate it with twenty minutes of adjusting features and installing software.
Another implication of GNOME's maturity is that apparently little can be done to improve it without radical changes. True, Ubuntu's new default theme may be more commercial than Fedora's in that it reminds people of Windows and OS X color scheme. Yet, overall, I have trouble seeing that Ubuntu's emphasis on usability for the past year has enhanced the GNOME desktop to any significant degree.
Fedora's treatment of GNOME is almost as usable -- and, at any rate, Ubuntu's in-house changes will likely be swept away (together with any advantages) by the release three months from now of GNOME 3.0, which will present an entirely different interface in the GNOME Shell.
No doubt that is why Ubuntu's next release will not include the GNOME Shell.
Of course, users might have other reasons for preferring either Ubuntu 10.04 or Fedora 13. For those who just want their desktop to work, the inclusion of proprietary extras might be a reason for preferring Ubuntu. Others, believing in free software ideals, might prefer Fedora's banning of proprietary elements. Similarly, Ubuntu's faster boot time might appeal to some, while the easy of editing with Legacy GRUB might be the deciding factor in favor of Fedora in some cases.
Only one thing seems sure: your preference of one over the other is going to be based on details that others might dismiss as trivial. Given the common origin in GNOME and the high degree of customization that GNOME encourages, the functional advantage of either distribution is usually going to be minimal at least ninety percent of the time.
To devoted fans, the differences in the distros may loom large, but I suspect that the rest of us are unlikely to agree. These days, a change of desktops within a distribution is probably going to seem a more disruptive change than switching from one GNOME-based distribution to another.