Wi-Fi is a trademark of the Wi-Fi Alliance for certified products based on the IEEE 802.11 standards (also called Wireless LAN (WLAN) and Wi-Fi). This certification warrants interoperability between different wireless devices.

The term Wi-Fi often is used by the public as a synonym for wireless Internet (WLAN); but not every wireless Internet product has a Wi-Fi certification, which may be because of certification costs that must be paid for each certified device type.

Wi-Fi is supported by most personal computer operating systems, many game consoles, laptops, smartphones, printers, and other peripherals.

WiFi, short for Wireless Fidelity and also known as 802.11, is a popular and inexpensive way to create wireless networks among computers and PDAs in home and offices.
WiFi offers many uses for both individuals and companies. Examples of applications abound: in a public place such as an airport, where the company's intranet can be consulted while waiting for a plane, in a medium sized company, where WiFi serves as the support for a local network installed in a building that has not been pre-equipped with cable, or even at home or in the garden, where one's computer can be connected to the Internet.

Hotspots are pockets of wireless access points that increasingly populate airports, coffee shops, corporate campuses, public transportation, and even homes. The underlying technology, called WiFi, can broadcast high-speed Internet access over a short distance of a few hundred feet. A portable computer or PDA equipped with a WiFi card can tap into the Hotspot and jump onto the Internet for wireless surfing, send and receiving emails, connecting to a corporate VPN, etc.

Wireless LAN:

A wireless LAN (WLAN) is a wireless local area network that links two or more computers or devices using spread-spectrum or OFDM modulation technology based to enable communication between devices in a limited area. This gives users the mobility to move around within a broad coverage area and still be connected to the network.

For the home user, wireless has become popular due to ease of installation, and location freedom with the gaining popularity of laptops. Public businesses such as coffee shops or malls have begun to offer wireless access to their customers; some are even provided as a free service. Large wireless network projects are being put up in many major cities. Google is even providing a free service to Mountain View, California[1] and has entered a bid to do the same for San Francisco.[2] New York City has also begun a pilot program to cover all five boroughs of the city with wireless Internet access.