Knox-Shaw is a small lunar impact crater that is located near the eastern limb , and lies on the eastern floor of the walled plain Banachiewicz. The rim is circular and the inner walls slope down to a small interior floor at the midpoint. It is not significantly eroded and has no other distinguishing features. (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.