A Wi-Fi network is a wireless communication system that allows devices like computers, smartphones, and tablets to connect to the internet without using physical cables. It uses radio waves to transmit data between a router and connected devices, enabling users to access online content from various locations within the network's range. Wi-Fi networks are commonly found in homes, offices, and public places, providing convenience and mobility. The strength and speed of a Wi-Fi connection can vary based on factors like distance from the router, obstacles, and the number of devices connected. Security measures, such as passwords, help protect the network from unauthorized access.