Any products tested and approved as "Wi-Fi Certified" (a registered
trademark) by the Wi-Fi Alliance are certified as interoperable with
each other, even if they are from different manufacturers. A user with
a "Wi-Fi Certified" product can use any brand of access point with any other brand of client hardware that also is certified. Typically, however, any Wi-Fi product using the same radio frequency (for example, 2.4GHz for 802.11b or 11g, 5GHz for 802.11a) will work with any other, even if not "Wi-Fi Certified."
Formerly, the term "Wi-Fi" was used only in place of the 2.4GHz 802.11b standard, in the same way that "Ethernet" is used in place of IEEE 802.3. The Alliance expanded the generic use of the term in an attempt to stop confusion about wireless LAN interoperability.
Also see the Wireless LAN Standards chart in the Quick Reference section of Webopedia.
Wi-Fi Wireless Fi-delity
Wi-Fi原是無線高傳真的縮寫，現被視爲802.11無線局域網絡的代名詞。Wi-Fi技術規格爲IEEE提出，經Wi-Fi聯盟認證後，可確保不同無線產品的互通。
1996年，美國網絡通訊設備大廠朗訊（Lucent）率先發起成立無線以太兼容性聯盟
（Wireless Ethernet Compatibility
Alliance，WECA），着手創立無線網絡協議（WLAN），發展起初發展不順，聲勢遠落藍芽（Blue-tooth）之後。1999年，WECA
更名爲Wi-Fi聯盟，再度架構一套認證標準，提出通行業界的無線網絡技術--802.11一系列規格，包括802.11.b、802.11.a、
802.11.等。
Wi-Fi作爲802.11b的暱稱，與以太網絡作爲IEEE
802.3的暱稱道理一樣。現階段，經過Wi-Fi聯盟兼容性測試的無線網絡產品，即使製造商不同，也可互通與兼容，如PCMCIA無線網卡、USB無線
模塊等。根據Wi-Fi聯盟數據顯示，自2000年聯盟開始進行認證以來，目前約有680項產品已獲得Wi-Fi認證，預估2003年底認證產品將超越千
項。
目前，Wi-Fi聯盟正大力推動Wi-Fi
Zone計劃，準備將Wi-Fi認證標誌延伸至提供公衆無線網絡服務的熱點（Hpt
Spot）應用。該聯盟也公佈未來標準的認證時程，如針對無線傳輸安全性的WPA（Wi-Fi Protected
Access）V2，也就是802.11i將於2004年第3季通過認證；而可提供VoIP及強化多媒體支持的802.11e，也同樣計劃在2004第3
季通過Wi-Fi認證。