RedHat

Unix is the first Operating system in the world, developed by Kem Thompson and Dennis Ritchie in 1969 at Bell Lab by AT&T Company

IBM     :           AIX

SGI      :           IRIX

HP       :           HP

Sun      :           Solaris

FSF :–> Free software foundation organization, they start a project by name GNU. The mail aim of this project is to develop such a O.S  that can run on any platform.

In 1991, a student Linus Tarvalds developed a kernel named Linus’s Kernel plus GNU application called Linux O.S

Linux is a open source technology.

Different companies that provide Linux in Market are Redhat, SuSe, Mandrake, Turbo, Knoppix etc.