The wifi full form is wireless fidelity which is a trademark of IEEE 802.11x term. WIFI is used for local area networking (LAN) of devices and internet access, allowing nearby devices to exchange data by radio waveform.
The name Wi-Fi, commercially used at least as early as August 1999 WIFI was named by the brand-consulting firm Interbrand . The name Wi-Fi has no further meaning, and was never officially a shortened form of “Wireless Fidelity”.
Nevertheless, the Wi-Fi Alliance used the advertising slogan “The Standard for Wireless Fidelity” for a short time after the brand name was created.