There are many different types of telephone. A telephone that can be carried around is called a mobile phone or cell phone. These became popular in the late 1980s. It has become common for people to carry mobile phones and in some places it is unusual to not have one. The majority are smartphones, which can be used as computers. Some mobile phones are able to make telephone calls using communications satellites instead of masts on the ground, which means people can make calls from anywhere in the world.