What do you do if you're not happy with the computer operating systems on the market? You build your own, of course. That's exactly what Linus Torvalds did. He created an open-source operating system: "open source" meaning that it's available to all (unlike proprietary systems tied to individual brands) and "operating system" meaning the computer's fundamental programming. His freely distributed, Intel-processor-based system is now used around the world. While Linux (pronounced LIH-nucks) began life primarily as a hobby for super geeks, it has made inroads into corporate life, particularly as an inexpensive substitute for high-priced Unix operating system-based Web servers. Linux is available from a number of vendors for several hardware platforms, including Intel x86, DEC Alpha, Sun Sparc, and Motorola PowerPC.

Local Area Network (LAN)

A local area network is a short-distance system used to link a group of computers together. The most commonly used form of LAN is the 10BaseT Ethernet. A piece of hardware called a hub serves as the common wiring point, enabling data to be sent from one machine to another over the network. LANs are typically limited to distances of less than 500 meters and provide low-cost, high-bandwidth networking capabilities within a small geographic area.