A pyramid is any three-dimensional polyhedron where the faces other than the base are triangular and converge on one point, called the apex.The base of a pyramid can be any polygon but is typically a square, leading to four non-base faces. The most famous pyramids are the ones found in Egypt.
There are three pyramids in Giza - there is the Khufu's Pyramid, Khafre's Pyramid and Menkaure Pyramid.
The Great Pyramid of Khufu at Giza is the largest of the pyramids of ancient Egypt, and was regarded by the ancient Greeks as one of the Seven Wonders of the World. Khufu (Cheops to the Greeks) ruled about 2589-2566 BC when the Old Kingdom of Egypt was nearing a peak of prosperity and culture. After his death, he was entombed in a pyramid that is astonishing for both its size and mathematical precision.
The people of ancient Egypt believed that death on Earth was the start of a journey to the next world. The embalmed body of the king was entombed in a chamber either underneath or within the pyramid to protect it and allow his transformation and ascension to the afterlife, and a place among the gods. Each of the Giza Pyramids had an adjoining mortuary temple where rituals for the dead king's spirit and for the Egyptian gods may have been carried out. This was linked by a causeway to a valley temple near the Nile floodplain that acted as an entrance to the complex. The Giza necropolis also includes pits for funerary boats, smaller subsidiary pyramids and numerous other tombs for the royal family and high officials.