Linux was started in 1991 when a graduate student in Finland named Linus Torvalds began a small project to learn about operating systems. As time passes, Linux was developed as a fully POSIX-complaint operating system for Intel microcomputers. Truly, Linux was not developed by any company, and is not owned by anyone. It was created by the Internet community, so it had been placed under the General Public License and freely distributed on the Internet.
Like Unix, Linux contains all the features of modern operating system including 32-bit protected-mode, preemptive multitasking, virtual memory, shared libraries, and TCP/IP networking. In addition, Linux can run on Intel 386, 486, and Pentium machines with PCI and VLB busses, and it also performs well on DEC's Alpha, and some other platforms.