The three main branches of Christianity are Catholic, Protestant and Orthodox. There are a large number of subdivisions under these main groups but these are the general titles.
There are multiple other types of Christians, states Catholic Resources. Some examples of these are Nestorian, Anglican, Marginal, Monophysite and Restorationist. The Protestant Christians are more commonly seen in America in modern day. Some may be referred to as non-denominational, while some connect to churches such as the Lutheran Church or identify as Calvinist Christians. The Orthodox Christians may also be called Eastern Christians. The Catholic Christians may also be called Roman Catholics, though many no longer affiliate with Rome.