Their are several answers to that. One was a tomb and a place to store their earthly goods, an riches needed for the next world, and a boat for the very long journey down the river to the other side! And to guard these things from thieves before they left on that trip! It was also a display of the power and riches they had in this world! OR immortality by lasting so long!

 Some of the pyramids were built as burial places for Egyptian royalty. They mave have represented a place or a stairway for them to ascend to the heavens. The contents of the pyramids included all sorts of items that were believed the deceased would need in the afterlife. Food, treasure, pottery, and even chariots and boats have been found in those pyramids that were not already plundered by looters.

Another thought is that the pyramids were meant to symbolize the mound on which Ra, the sun god, or creator was born. In any event, the pyramids of Egypt are an examples of incredible feats of engineering.

 They built the pyramids in recognition and to remember the most important and respected pharohs of that time.

 The eygptians built the pyramids to leave a message for us. Hundreds of pyramid around the world and their meanings were destroyed by neo-colonialism. That was the genocidal conquerments that Europeans imposed on the world. There is a message there we will never get to know but ask yourself this WHY AFTER ALL THESE THOUSANDS OF YEARS AND "NEW" TECHNOLOGY, WHY CAN'T THE PYRAMIDS BE RECREATED. I've read that some of the first pyramids had gold model airplanes and cars but we let the government tell us everything we do is sooooo "new". The pyramids were above all a sign of peace and a message that all people are the same thing and live under the same god. We will know what they meant because soon they'll be able to finally recreate the geometrically perfect eygptian pyramid. And I guess they same bs they had to deal with on that day we will be in the face of.

 They built them because there faros told them to

 There is a theory that the pyramid was like a pathway to heaven, it has been discovered that pyramids contained a shaft from the burial room, right out to the outside of the pyramid. At certain points in the day, this was lined directly with the sun. We believe that this was meant to assist the sole on its journey to the heavens.

 Some of the pyramids were built for Egyptian Pharaohs and Kings as burial places. The first pyramid was built as a burial place King Djoser in 2630 BC had a step pyramid which represented the steps leading up into the heavens for the afterlife. The pyramids contained food, treasure, pottery, and even chariots or boats were stored in the chambers, which the ancient Egyptians believed would help in the afterlife. Grave robbers have stole most of the artifacts of a lot of pyramids by 1000 BC.