If you mean the three pyramids in the Giza Necropolis...It is generally believed the Great Pyramid was built as the tomb of Fourth dynasty Egyptian King Khufu.
South-west of the Great Pyramid lies the slightly smaller Pyramid of Khafre, one of Khufu's successorsand a few hundred metres further south-west is the Pyramid of Menkaure, Khafre's successor.
ss2 has correctly given the Egptian names, or as close as we can decipher them - you'll also find the three referred to as Cheops, Chephren and Mycerinus, probably via Herodotus (bless him)...