Catenary curves are formed when a homogeneous cable is suspended by its endpoints. The word catenary is derived from the Latin word for "chain." The mathematics of the curves are described by a hyperbolic function.
Catenary curves can also be seen in lots of structures.
St. Louis Arch
Tarptent ridgelines are true catenary curves. This design element gives Tarptents exceptional strength, sag resistance, and wind-shedding ability.