Name: Debian GNU/Linux

License: General Public License

Website: www.debian.org

Characteristics:

• Defines enterprise package management
• Huge number of features
• Secure, stable and scalable
• Free

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Name: RedHat Enterprise Linux

License: Commercial License

Website: www.redhat.com

Characteristics:

• Enterprise-class operating system
• Integrates well with middleware application stacks like JBoss

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Name: Ubuntu Linux

License: General Public License

Website: www.ubuntu.com

Characteristics:

• Debian with added polish for the Desktop
• Regular releases
• Easy to install

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Name: CentOS

License: General Public License

Website: www.centos.org

Characteristics:

• Almost 100% binary compatible with RedHat Enterprise Linux
• Free

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Name: OpenBSD

License: BSD

Website: www.openbsd.org

Characteristics:

• Renowned for rigorous development methodology
• Perfect for secure internet connectivity
• Free

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Name: FreeBSD

License: BSD

Website: www.freebsd.org

Characteristics:

• Reliable and robust
• Known for length of server uptime
• Perfect for web servers
• Free

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Name: NetBSD

License: BSD

Website: www.netbsd.org

Characteristics:

• Highly portable
• Perfect for embedded system
• Often the starting point for the porting of other operating systems to new computer architectures

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Name: Mandriva

License: GPL with commercial variants

Website: www.mandriva.com

Characteristics:

• French Linux distribution
• RPM-based
• Known for early incorporation of 3D desktop effects

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Name: Fedora Core

License: GPL

Website: www.fedoraproject.org

Characteristics:

• Free, popular Linux distribution based on Red Hat Enterprise Linux
• RPM-based
• Used as a testing ground for features prior to their incorporation into RHEL

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Name: OpenSolaris

License: Mainly GPL

Website: www.opensolaris.org

Characteristics:

• Open Source implementation of Solaris
• Developed to help build a development community around Solaris
• Default desktop is Sun's Java Desktop

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Name: Gentoo

License: GPL

Website: www.gentoo.org

Characteristics:

• Well documented if somewhat baroque Linux distribution
• Uses a BSD-like ports system for package management
• Bleeding-edge distribution for enthusiasts that takes a lifetime to compile

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Name: Darwin

License: Apple Public Source

Website: Darwin website

Characteristics:

• Develops the core set of components upon with Mac's OSX is based
• Interesting for OSX enthusiasts

Sirius rating: