A wireless adapter is a device that allows computers and other electronic devices to connect to a wireless network, such as Wi-Fi. It can be built into the device or added externally via a USB port. Wireless adapters convert data from the device into radio signals, enabling communication with a router. These adapters come in various forms, including USB sticks and internal cards. They support different wireless standards, such as 802.11n and 802.11ac, which determine the speed and range of the connection. By using a wireless adapter, users can access the internet without the need for physical cables.