There is a tradition in Japan to take off shoes when entering the house. There is a special area just inside the front door where shoes are removed. It’s called “genkan”. After taking their shoes off, Japanese people usually put on slippers. It’s done in order to prevent socks from getting dirty and feet – from getting cold. However, it’s forbidden to enter a traditional Japanese tatami room in slippers. But socks and bare feet are welcome!
A fact that’s really amazing: in some Japanese houses you will be asked to use a special pair of slippers when visiting a bathroom. A person should remove home slippers and put on bathroom ones. There is only one pair of them and it’s used by all hosts and guests. A visitor should not forget to put home slippers back on. If he or she doesn’t do it, he or she’ll get into a very confusing situation. Japanese hosts will be nearly shocked and consider the foreigner to be impolite and absolutely careless.
It’s also normal and customary to remove shoes when entering shrines and temples, traditional inns and hot springs resorts.