The first Pyramid was built by Pharaoh Dzoser of the Third Dynasty, but origins can be traced to the second Dynasty Pharaoh Khasekhemwy, he was buried in a Mastaba.
It is thought that Imhotep, Architect of the Step Pyramid, made the pyramid by placing mastabas on top of each other, each one smaller than the next, making a "Starway to the Heavens," as some Scholars say.
The Step Pyramid then evolved into a "True" Pyramid, Such as the ones at Giza.
All the stones used in Khufus Pyramid at Giza is almost Equal to all the stone used in the fifth and sixth Dynasty pyramids combined!
I have a new section about the Great Pyramid and I hope to have a few more up soon! check back for updates!