What is Linux? (Copied from www.linux.org)
Linux is a freely-distributable, independent Unix-like operating system for x86, Motorola 68k, Digital Alpha and Motorola PowerPC machines. It is an implementation of the POSIX specification with which all true versions of Unix comply. The Linux kernel uses no code from AT&T or any other proprietary source, and much of the software available for Linux is developed by the Free Software Foundation's GNU project.

It supports a wide range of software, including X Windows, Emacs, TCP/IP networking (including SLIP/PPP/ISDN), the works. Many people have executed benchmarks on 80486 Linux systems and found them comparable with mid-range workstations from Sun and Digital.