Titov is a small lunar impact crater on the far side. The most unusual aspect of this crater is that it is located entirely within the Mare Moscoviense, one of the few maria found on the far side. It lies to the northwest of the crater Komarov, in the northern half of the mare. It is named for cosmonaut Gherman Titov, the second person to orbit the Earth. (wikipedia entry)
A crater is a circular depression likely created by an impact event. On the Moon they are named after deceased scientists, polar explorers, astronauts or cosmonauts.