A pyramid is a human-made mountain: a monumental structure with a triangular or square base and sides that slope to a point at the top. The three pyramids at Giza, in Egypt, are some of the most ancient structures in the world. Pyramids are layered structures; they were constructed starting with a large square base and building one layer at a time until they reached the top. The large square base creates a very stable structure.
Like a mountain, a pyramid is often used as a metaphor for the stages in human development: As you rise in the pyramid, you come closer and closer to maturity and self-actualization.
A pyramid can also symbolize a work structure, like the upside-down tree you see in an org chart. The boss sits at the top of the pyramid and workers are arranged in a hierarchy below.
A pyramid scheme, also known as multi-level marketing, is a kind of pyramid constructed from the top down. The founders sit at the top of the pyramid, and recruit people to inhabit the layers below them. Each new recruit is required to generate sales by recruiting people to work below them in the pyramid.
Author and consultant Barbara Minto coined the term “pyramid principle” in her book of the same name, to describe a writing method where a main topic sentence sits at the top of the pyramid, and the essay or story builds by progressively adding detail, layer by layer, until the right level of granularity is achieved.