When I hear ‘pyramids’ I think of three things in this order: the famous pyramids in Egypt, the 3-dimensional geometric shape known as a pyramid, and pyramid schemes where people join up at the bottom and the money channels up to the person at the top. Not a good idea to join one by the way.

Besides those three things, nothing really comes to mind. Hope this helps.

Two reasons: they are the first I learned about; and they are in the simplest form of a rectangular pyramid, with little variation from the classic simple geometric shape.

(I’m wondering how someone earns “best answer” from you.)