MASTABA

A 'mastaba' was a flat-roofed, mud brick, rectangular building with inward sloping sides that marked the burial site of many eminent Egyptians of Egypt's ancient period.
''Mastaba'' comes from the Arabic for bench, because when seen from a distance it looks like a mud bench . Inside a mastaba, a deep chamber was dug into the ground and lined with stone or mud bricks. The body would reside in this deep chamber. Above ground, the mud was piled up over the mastaba to mark the grave and to keep grave robbers away, oblong in a shape with a length approximately 4 times its width. Although this provided a much grander tomb, it was also a much cooler tomb. This upset the early priests as it allowed the bodies to decompose due to the fact that water no longer evaporated, preventing desiccation of the bodies.
The Mastaba was the standard tomb type in early Egypt (the predynastic and early dynastic periods.)
When a mastaba was built for the burial of the Third Dynasty king Djoser, the architect Pussiothep enlarged the basic structure to be a square, then built a similar, but smaller, mastaba-like square on top of this, and added a fourth, fifth, and sixth square structure above that. The resulting building is the Step Pyramid, the first of the many pyramidal tombs which succeeded it.
Thus the mastaba is the first step towards the more famous Pyramids. The body still resides below in an underground chamber instead of inside the step pyramid (like the mastaba.)