Linux is a widely-used open source operating system based on the Unix operating system. Open source means that the source code that comprises this gigantic program may be freely modified, used, and redistributed by anyone. The name “Linux” comes from the Linus Torvalds, the Finnish computer engineer who wrote essential components of the software in 1991 at the age of 22. He later obtained a master’s degree for this software. Torvalds is still very actively involved in Linux, and is the final authority on incorporating extensions into the operating system.
Linux is used in a wide range of embedded devices such as cell phones and consumer electronics, industrial automation, and medical equipment. It also runs a wide variety of computers ranging from personal computers to servers and supercomputers. Linux is a major player in the rapidly expanding netbook market, very light and inexpensive portable computers.
System administrators often communicate with Linux via the text-based command line interface. You haven’t seen anything until you’ve seen a techie enter a series of arcane commands at what seems to be the speed of light. This operating system supports a variety of graphical user interfaces (GUIs) that often resemble Microsoft Windows. Linux fans will tell you that their interface (and everything else of theirs) is light years ahead of Microsoft offerings.
A Linux distribution, call it a “distro” if you want to sound like an insider, is a version of the operating system and selected applications. There are said to be more than 300 distros, which are all at least slightly different. Widely used distributions include Red Hat, Debian, and recently Ubuntu whose name is Zulu for humanity. Ubuntu claims to have about 30% of the Linux desktop installations. One of my favorites is Damn Small Linux which can run under Windows, even on old, clunky computers. Some of the bigger distributions aren’t free of cost, but they are still quite inexpensive when compared with Microsoft or Macintosh operating systems.
Linux is a great environment for writing programs. It supports numerous programming languages and other programmers’ tools. But you don’t have to be a programmer to use it. An increasing number of people go for Open Office, an open-source competitor to Microsoft Office. There are said to be thousands of free software applications written for Linux. Linux is an essential component of the LAMP software suite. Among the other members of this family are Apache, the most widely used web server software, MySQL, a major database management system, and PHP, the most widely used web programming language. To be fair, I must tell you that it’s possible to run Apache, MySQL, and PHP on Windows computers.
While Linux is estimated to have less than 2% of the desktop market, it controls about 12% of the server market, and is by far the major operating system for supercomputers. Tivo uses a specialized version of Linux. The One Laptop Per Child project in developing countries that hopes eventually to supply several hundred million children with a netbook relies on Linux (but there is a Windows option.)