Wi-Fi is a trademark of the Wi-Fi Alliance for certified products based on the IEEE 802.11 standards. This certification warrants interoperability between different wireless devices.
In some countries (and in this article) the term Wi-Fi is often used by the public as a synonym for IEEE 802.11-wireless LAN (WLAN).
Not every IEEE 802.11 compliant device is certified by the Wi-Fi Alliance, which may be because of certification costs that must be paid for each certified device type. The lack of the Wi-Fi logo does not imply that a WLAN-device is incompatible to certified Wi-Fi-devices.
Wi-Fi is supported by most personal computer operating systems, many game consoles, laptops, smartphones, printers, and other peripherals.