Linux/UNIX Operating Systems

SuSE Linux is a Linux operating system by Novell. It is built on top of the Linux kernel and is distributed with system and application software from various projects.

Red Hat is the world's leading open source technology solutions provider with offerings including Redhat Enterprise Linux, open source applications........

Fedora is an RPM-based, general purpose operating system built on top of the Linux kernel, developed by the community-supported Fedora Project and sponsored by Red Hat. The Fedora Project's mission is to lead the advancement of free and open source software and content as a collaborative community.
One of Fedora's main objectives is not only to contain software distributed under a free and open source license, but also to be on the leading edge of such technologies.

CentOS is a community-supported operating system software based on Red Hat Enterprise Linux. It is available free of charge.
CentOS developers use Red Hat's source code to create a final product very similar to Red Hat Enterprise Linux. Red Hat's branding and logos are changed because Red Hat does not allow them to be redistributed.

Ubuntu is a computer operating system based on the Debian GNU/Linux distribution and is distributed as free and open source software with additional proprietary software available. Ubuntu provides an up-to-date, stable operating system for the average user, with a strong focus on usability and ease of installation.

Debian is an operating system composed of software packages released as free and open source software especially under the GNU General Public License and other free software licenses. The primary form, Debian GNU/Linux, which uses the Linux kernel and GNU OS tools, is a popular and influential GNU/Linux distribution. It is distributed with access to repositories containing thousands of software packages ready for installation and use. Debian can be used as a desktop as well as server operating system.

Slackware OS is a free and open source operating system. It is one of the earliest GNU/Linux distributions and is the original Linux distribution. Slackware was created by Patrick Volkerding of Slackware Linux, Inc. in 1993. The current stable version is 13.0, released on August 26, 2009.

Unix FreeBSD: Berkeley Software Distribution (BSD, sometimes called Berkeley Unix) is the UNIX operating system derivative developed and distributed by the Computer Systems Research Group (CSRG) of the University of California, Berkeley.