FreeDOS 1.0

Ubuntu Studio is aimed at the GNU/Linux audio, video and graphic enthusiast as well as professional.

PinguyOS is a Linux distribution that is built on the Ubuntu framework.

Solaris is a Unix operating system originally developed by Sun Microsystems.

DoudouLinux is specially designed for children to make computer use as easy and pleasant as possible for them and for their parents too!. DoudouLinux provides tens of applications that suit children from 2 to 12 years old and gives them an environment as easy to use as a gaming console. Kids can learn, discover and have fun without Dad and Mum always watching!

Haiku is an open source operating system currently in development designed from the ground up for desktop computing. Inspired by the Be Operating System, Haiku aims to provide users of all levels with a personal computing experience that is simple yet powerful, and void of any unnecessary complexities.

Chromium OS is an open-source project that aims to build an operating system that provides a fast, simple, and more secure computing experience for people who spend most of their time on the web

Super-fast and great-looking, Ubuntu is a secure, intuitive operating system that powers desktops, servers, netbooks and laptops. Ubuntu is absolutely free.

Arch Linux (or Arch) is a Linux distribution intended to be lightweight and simple. The design approach of the development team focuses on simplicity, elegance, code correctness and minimalism.

BackTrack-Is a Linux distribution distributed as Live cd or Usb for penetration testing.BackTrack provides penetration testers a comprehensive collection of security related tools, support live cd and live usb and permanent installation also.BackTrack provides Mozilla, Pidgin, K3B, XMMS .You can create personalized distributions by including customizable scripts, additional tools and configurable kernels.

Kubuntu is a free, user-friendly operating system based on the K Desktop Environment and on the award winning Ubuntu operating system. With a biannual release cycle and at least 18 months of free security updates for each release, it is the secure, stable computing environment you've been waiting for.

FreeBSD is a 4.4BSD-Lite based operating system for Intel (x86 and Itanium®), AMD64, Sun UltraSPARC® computers. FreeBSD provides advanced operating system features, making it ideal across a range of systems, from embedded environments to high-end multiprocessor servers.

YLMF open source operating system (Ylmf OS) English Edition is released!The interface operation is clean and clear.The adjustment and creation is based on the user's experience and 

The purpose of Linux Mint is to produce a modern, elegant and comfortable operating system which is both powerful and easy to use.It's both free of cost and open source. It's safe and reliable. Thanks to a conservative approach to software updates, a unique Update Manager and the robustness of its Linux architecture, Linux Mint requires very little maintenance.

CentOS is an Enterprise-class Linux Distribution derived from sources freely provided to the public by a prominent North American Enterprise Linux vendor. CentOS exists to provide a free enterprise class computing platform to anyone who wishes to use it.

ReactOS is a computer operating system intended to be binary compatible with application software and device drivers made for Microsoft Windows NT versions 5.x and up (Windows 2000 and its successors). It is claimed to be composed entirely of free software, by means of a complete clean room reverse engineering process, with an extensive on-going audit, being undertaken to protect against claims made by those outside the project.

Hiren’s Boot CD is an all-in-one bootable CD solution that contains a load of useful tools you can make use of in a variety of situations. I am talking about hard drive failure, virus infections, partitioning, password recovery and data recovery. HBCD (as Hiren’s Boot CD is called) is a God-send in situations like these. It has a multitude of tools divided into a number of categories like partitioning tools, backup, recovery and BIOS/CMOS tools to name a few.

Anonymous hackers have unconfined their OS with the name “Anonymous- Operating System Anonymous-OS 0.1”. It is an ubuntu-based distribution and created under Ubuntu 11.10 and uses mac desktops. Live USB can be created with Unetbootin.

Zorin OS is an Ubuntu based Linux distribution that replicates the Windows graphical user interface to make it easier for Windows users to use. Zorin OS is faster than Windows, more reliable than Windows, open source and free.

Being based on Ubuntu, moonOS will basically run as well, if not better, on any decent, current hardware; by using Enlightenment instead of Gnome, your experience with moonOS should actually be much, much more snappy :) - Enjoy freedom at blazing speeds! 700 MHz x86 processor 384 MB of system memory (RAM) 8 GB of disk space Graphics card capable of 1024x768 resolution A network or Internet connection is needed if you want to download extra software.

Fedora is a Linux-based operating system, a collection of software that makes your computer run. You can use Fedora in addition to, or instead of, other operating systems such as Microsoft Windows™ or Mac OS X™. The Fedora operating system is completely free of cost for you to enjoy and share.

Xubuntu is an elegant and easy-to-use operating system. Xubuntu comes with Xfce, which is a stable, light and configurable desktop environment.

PCLinuxOS was founded in October 2003. The flagship product, the PCLinux operating system, is a free, easy-to-use Mandriva Linux-based operating system for the home. PCLinuxOS was founded by Texstar, and is headquartered in Houston, Tx.

Mandriva Linux (formerly Mandrake Linux) is a Red Hat-based operating system created by the French software company Mandriva (formerly Mandrakesoft). It is the result of the technical merging of the former Mandrake Linux and Conectiva distributions. Mandriva is released in both desktop and server flavors.

Kali linux is the most advanced and versatile penetration testing distribution that has ever been created.