UGG is an American brand of snow boots.
UGG is actually the general name for this type of wool boots originating from Australia, meaning "Ugly Boots". In 1978, an Australian surfer Brian established the UGG brand in Southern California. Brian was the first to bring UGG boots to the United States, but their appearance was not appreciated.
In 1995, Deckers Outdoor Sports Company took over the business. Hollywood stars put on snow boots and became popular in the United States. After that, they quickly gained recognition in many countries.
Extended information:
Snow boots first became popular among Australian shearers. Shearers remove a small piece of sheepskin from the sheep, trim it and sew it to make boots that cover the feet. They call these shoes "ugly sheepskin boots" (ugly boots).
Australia is known as "a country riding on the back of a sheep", and it goes without saying that the quality of the wool it produces goes without saying. Later, during World War II, they were used by the Australian Air Force as special military boots to keep out the cold and keep warm.
Reference source: Baidu Encyclopedia-UGG