Open source Linux OS’s: 1

Courtesy: wikipedia
Debian-based
Debian is a distribution that emphasizes free software. It is supported on many hardware platforms. Debian and distributions based on it use the .deb package format and the dpkg package manager.

64 Studio
Attempts to specialize in audio and video production on AMD64 workstations.
AbulÉdu
For education purposes
Baltix
For Lithuanian and Latvian languages
BeatrIX
A compact distribution from the Czech Republic that focuses on providing a user-friendly desktop environment.
Corel Linux
Shortlived desktop distribution
DeMuDi
For multimedia production
Dreamlinux
A Brazilian Linux distribution based on Morphix, Elive, Debian and Kanotix. It has a GUI that bears a strong similarity to that of Apple Computer's Mac OS X.
eBox
Router/Firewall and NAS/PDC
Elive
A Live CD and Distribution featuring Enlightenment as the only window manager. Aims to be intuitive and easy to use.
Feather Linux
Shares similar goals as Damn Small Linux, but not based on it (Feather is more closely related to Knoppix). Uses Knoppix-based hardware detection and the Fluxbox window manager. Compatible with Debian packages (.deb).
Finnix
A small system administration Live CD that is available for multiple architectures.
G2Linx
Realtime distribution for industrial automation
Gibraltar
Router/firewall distribution.
gnuLinEx
A distribution promoted by the government of Extremadura, Spain.
Kanotix
An installable live CD for desktop usage using KDE, focusing on convenient scripts and GUI for ease of use.
Knoppix
The first Live CD (later DVD) version of Debian GNU/Linux.
LEAF Project
The Linux Embedded Appliance Firewall. A tiny primarily floppy-based distribution for routers, firewalls and other appliances.
LiMux
An ISO 9241 industry workplace certified Linux distribution, deployed at the City of Munich, Germany.
Linspire
Desktop-oriented distribution, previously called Lindows. Focuses on a proprietary software application manager obtained via a paid (CNR) subscription.
The Linux Router Project
A defunct floppy-based distribution for routers and firewalls.
Maemo
A development platform for hand held devices such as the Nokia N800 and N810 Internet Tablets and other Linux-based devices. Parts of maemo (particularly the Hildon UI) are also planned to be used in the Ubuntu Mobile and Embedded Edition.
MEPIS
Installable live CDs
NepaLinux
A Debian and Morphix based distribution focused for desktop usage in Nepali language computing.
OpenZaurus
Debian packages and ROM image for the Sharp Zaurus PDA.
Outernet Server
A modified version of Debian that installs preconfigured and is specifically meant for a High speed multimedia Networks.
Parsix GNU/Linux
Installable live CD based on Kanotix and Debian
PingOO
French distribution aimed at local communities, public organizations, schools, etc. It comes in three editions: PingOO Communication Server, PingOO Secure Server and PingOO File Server.
PSUbuntu
A Ubuntu distribution intended for the Playstation 3.
Progeny Componentized Linux
Distribution from Progeny Linux Systems which was also founded by Debian founder Ian Murdock.
Rxart
Desktop-oriented distribution. Focused on providing proprietary software.
Salgix
Distribution developed and maintained by GMSI (Gemini Microsystems International) for its line of Visual Computing workstations.
Skolelinux
A distribution from Norway. It is provided as a thin client distribution for schools.
sidux
Multilingual desktop-oriented Live CD based on Debian unstable (Sid)[1] providing a graphical installer. It is a rolling release, so once installed, it can be kept up-to-date with updates from the Debian Sid and sidux repositories.
Storm Linux 2000
Distribution from Stormix
Symphony OS
Includes the Mezzo desktop environment. Previous versions were based on Knoppix.
Trisquel
Created in Galicia (Spain). It has support for old PCs, includes a 3D desktop with Compiz.
Linux Tiger
Designed to be similar to Mac OS X.
Tuquito
Created in Argentina
Ubuntu
A distribution sponsored by Canonical Ltd as well as receiving major funding from South African Mark Shuttleworth. Aims to offer a complete and polished desktop on a single CD.
UserLinux
Commercial distribution that would have included GNOME. It was never published.
Xandros Open Circulation Edition
based on Xandros 3.0 Standard Edition with the exception of DVD burning being disabled and CD burning restricted to a maximum speed of 4X.
Xebian
For the Xbox home gaming console.