Regular Flavors

Arch

 * Difficulty: Intermediate
 * Desktop: Xfce
 * Package Manager: Pacman
 * Description: Arch Linux keeps it simple by being a lightweight and flexible distribution. It employs BSD-like techniques and is on a rolling release.
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CentOS

 * Difficulty: Advanced
 * Desktop: Gnome
 * Package Manager: RPM
 * Description: Cent OS is “a free enterprise class computing platform” and is 100% compatible with Red Hat Enterprise Linux.
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Crunchbang

 * Difficulty: Beginner/Intermediate
 * Desktop: Openbox
 * Package Manager: DEB
 * Description: Crunchbang is Ubuntu but with the lightweight Openbox desktop and GTK+ applications. It is designed for speed and functionality.
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Dreamlinux

 * Difficulty: Beginner/Intermediate
 * Desktop: Xfce
 * Package Manager: DEB
 * Description: Dreamlinux is a Debian based distribution that mimics the look of Mac OS X.
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Easy Peasy

 * Difficulty: Beginner
 * Desktop: Gnome
 * Package Manager: DEB
 * Description: Easy Peasy is an Ubuntu based distribution designed for netbooks. It has a mixture of open source and proprietary software installed.
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Edubuntu

 * Difficulty: Beginner
 * Desktop: Gnome
 * Package Manager: DEB
 * Description: Edubuntu is Ubuntu but with a tightly integrated suite of education programs.
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Gentoo

 * Difficulty: Advanced
 * Desktop: Xfce
 * Package Manager: Portage
 * Description: Gentoo is a versatile distribution, with characteristics from BSD, that is designed for advanced Linux users. It has no pre-compiled software.
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gNewSense

 * Difficulty: Beginner
 * Desktop: Gnome
 * Package Manager: DEB
 * Description: gNewSense is a FSF sponsored distribution that is entirely free (libre) and includes GNU programs.
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Kubuntu 9.04

 * Difficulty: Beginner
 * Desktop: KDE
 * Package Manager: DEB
 * Description: Kubuntu is Ubuntu but with the KDE desktop. It is 100% compatible with Ubuntu.
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Mandriva

 * Difficulty: Beginner
 * Desktop: KDE
 * Package Manager: RPM (urpmi)
 * Description: Mandriva, formerly known as Mandrake, is a well established distribution that is suitable for general purpose use.
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Mint 7

 * Difficulty: Beginner
 * Desktop: Gnome
 * Package Manager: DEB
 * Description: Mint is an Ubuntu based distribution that provides extras, proprietary and open source alike, to create a better “out-of-the-box” feel. It is 100% compatible with Ubuntu.
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Mythbuntu

 * Difficulty: Intermediate/Advanced
 * Desktop: Xfce
 * Package Manager: DEB
 * Description: Mythbuntu is Ubuntu but with added support for MythTV.
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PCLinuxOS

 * Difficulty: Beginner
 * Desktop: KDE
 * Package Manager: RPM (APT)
 * Description: PCLinuxOS is a distribution designed for ease of use for homes and small businesses.
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Sabayon

 * Difficulty: Advanced
 * Desktop: KDE
 * Package Manager: Entropy
 * Description: Sabayon is a Gentoo based distribution that offers pre-compiled software.
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Ubuntu 9.04

 * Difficulty: Beginner
 * Desktop: Gnome
 * Package Manager: DEB
 * Description: Ubuntu is the most popular distribution. It is easy to use yet extremely versatile.
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Ubuntu Studio

 * Difficulty: Beginner
 * Desktop: Gnome
 * Package Manager: DEB
 * Description: Ubuntu Studio is Ubuntu but integrated programs for multimedia creation.
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Vector

 * Difficulty: Beginner/Intermediate
 * Desktop: Xfce
 * Package Manager: TLZ
 * Description: Vector Linux is a lightweight distribution that can be customized to meet nearly anyone's needs.
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Xubuntu 9.04

 * Difficulty: Beginner
 * Desktop: Xfce
 * Package Manager: DEB
 * Description: Xubuntu is Ubuntu but with the Xfce desktop. It is 100% compatible with Ubuntu.
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Zenwalk

 * Difficulty: Intermediate
 * Desktop: Xfce
 * Package Manager: TGZ
 * Description: Zenwalk is a Slackware based distribution that is “fast and slim.” It has one program for one purpose.
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31 Flavors of Linux (Plus 4)