Wireless communication is the transfer of information or power between two or more points that are not connected by an electrical conductor. The most common wireless technologies use radio waves.The term wireless has been used twice in communications history, with slightly different meaning.

Types of Wireless Networks.
There are basically three different types of wireless networks –
LAN and PAN:
Wireless Wide Area Networks (WWAN): WWANs are created through the use of mobile phone signals typically provided and maintained by specific mobile phone (cellular) service providers.

Wireless works because an electromagnetic wave, passing through the air at the speed of light, can create - or 'induce' - an electrical signal in an aerial. ... So in a radio system, information is sent from one place - the transmitter - and picked up in another - the receiver - using an electromagnetic wave to carry it.
A WLAN can be either an extension to a current wired network or an alternative to it. WLANs have data transfer speeds ranging from 1 to 54Mbps, with some manufacturers offering proprietary 108Mbps solutions. The 802.11n standard can reach 300 to 600Mbps.
While wireless LANs refer to any local area network (LAN) that a mobile user can connect to through a wireless (radio) connection; Wi-Fi (short for "wireless fidelity") is a term for certain types of WLANs that use specifications in the 802.11 wireless protocol family.