LI-FI is a wireless communication technology that uses visible light communication and light-emitting diodes (LEDs) to transmit data. It provides higher speeds and more secure connectivity than traditional radio wave Wi-Fi. While LI-FI has advantages like providing internet on planes and underwater, it also faces limitations like inability to pass through objects and interruptions from external light sources. Overall, LI-FI has great potential and is expected to become an important part of wireless internet access in the future.