Source: University of Patras
Wi-Fi, short for "Wireless Fidelity" is a term for certain types of Wireless Local Area Network (WLAN) that uses specifications in the 802.11 family. In general, the wireless technologies are used for the replacement or the expansion of the common wired networks. They possess all the functionality of wired LANs but without the physical constraints of the wire itself. The wireless nature inherently allows easy implementation of broadcast/multicast services. When used with portable computing devices (e.g. notebook computers), wireless LANs are also known as cordless LANs because this term emphasizes the elimination of both power cord and network cable (Tanenbaum (2003)).