A teahouse or tearoom is a place for drinking tea. But the teahouses are different in different countries because of their different cultures.
In China, a teahouse is traditionally like the American "café". People go to teahouses to chat with friends, make friends, and enjoy tea. Young people often meet at teahouses for dates. The Guangdong style teahouses are very famous in China and in the world. These teahouses not only offer tea, but also dim sum, so people can eat different kinds of food when they drink tea. People call these kinds of teahouses "chalou".
In Japan, a teahouse means a place for holding Japanese tea ceremonies. Many Japanese teahouses are really traditional and only the people who have been invited can enter them.
In Tajikistan, there are also many teahouses. Tajikistan is a small country in the middle of Asia. In this country, the largest teahouses are usually Chinese style teahouses. Lots of people like drinking tea there.
In Egypt, teahouses are usually called coffee houses. People can drink coffee as well as tea and tisane. Tisane is highly popular in Egypt.
In the UK, Canada and the US, a tearoom is a small room or restaurant where people can have light meals. A customer might expect to receive cream tea, which is also a kind of afternoon tea.