What is the plug of the hotel socket for?

The sockets in the hotel are all humanized. There is a plug with one end plugged into the socket and the other end with USB interface. This is very convenient. Our hotel guests don't have a charger, but as long as they have a charging cable, they can directly plug the USB port into the plug and plug it into the socket to charge, and they can charge several different appliances such as mobile phone pad charging treasure.