WEP is short for Wired Equivalent Privacy, a security protocol for a wireless local area network (WLAN) defined in the IEEE 802.11b standard. WEP is designed to provide a wireless LAN with a level of security comparable to that of a wired LAN.
WEP was the standard set in 1999 and since then hackers have devised ways to exploit WEP security flaws. The most widely recommended solution to WEP security problems is to switch to WPA or WPA2. Either is much more secure than WEP.