Wi-Fi

Wi-Fi doesn't stand for anything, it was dubbed "Wi-Fi" because that's easier to remember than 802.11b. It basically refers to wireless Internet access. 

On a more technical level, Wi-Fi is a high-speed wireless networking standard (at 11Mbps and increasing to 20Mbps), and a leading RF technology (originally backed by Apple and 3Com). It refers to QoS in the continuous transmission of high-bandwidth video and multimedia information. Wi-Fi differs from HomeRF in that it repeatedly pushes signals through broader bands of frequency within the radio frequency spectrum. It differs from Bluetooth in that it is designed to serve the wireless LAN market (for example coffee houses and airports) rather than the more personal space that Bluetooth reaches.

Wi-Fi gives millions of computers wireless access to the Internet at broadband speeds in offices, homes and cafes. The limitation is that it's typically designed to allow wireless access within only about 300 feet of a radio transmitter plugged into a broadband Internet connection, like cable or DSL. It means you can't just open your laptop anywhere you happen to be and tap into the Internet. The next-generation wireless app, WiMax, intends to solve these contraints.

Wi-Fi wireless networks originally came in two speeds: "b" (the first version to gain public acceptance) and "g" (which is faster and backwards compatible with b). There is a third standard called "n" but like most new standards, it takes time to create and adopt a standard, and more time for it certified and sold (in this case resulting in "pre-n" and "draft-n" products to be sold). In addition to these standards is "MIMO" (Multiple-Input Multiple-Output), a key component of the "n" standard. MIMO is a technique that can greatly improve range and speed by capturing formerly stray parts of a wireless signal and merging them.