Operating Systems in Opensource based

Open Source Operating systems in many companies are inventing new technologies,
Mobile os is the Android to capture the mobile market,
PC and Laptop in to ocupy the Ubuntu linux(unix) based operating system.
List of the Some Open source Operating Systems :

Android	operating system derived from Linux	URL
FreeBSD	operating system derived from Unix	URL
Linux	family of Unix-like operating systems	URL
OpenIndiana	a free Unix-like operating system	URL
ReactOS	operating system built on Windows NT architecture	URL
Haiku	Free and open source operating system compatible with BeOS	URL