The WPS button on a Wi-Fi router allows a user to connect to a wireless network without needing to enter a security code. WPS stands for Wi-Fi Protected Setup and works only on networks using WPA Personal or WPA2 Personal security.
The WPS button is most useful for connecting devices to a Wi-Fi network when the security code is not available. There is typically a very short window of time after pressing the WPS button during which the device can connect without a security code. While routers with a WPS button make device connection quick and convenient, there is also some security risk involved.