ELI5: Explain Like I'm 5

Folium of Descartes

Folium of Descartes is a fancy name for a curvy line. It looks like a horseshoe and was first described by the famous French mathematician Descartes. It's made by tracing a curve that never crosses itself, kind of like making a pretzel. The curve is sometimes used in math and science to represent real-life things, like the shape of the Earth or a stream of water.