Hey, Guys! I wonder what applications of Ramsey's famous theorem there exist apart from such cases as: 1) constructions of functions in the domain of natural numbers to check some properties of sequences of real numbers. 2) propositions about points in convex postition (Erdos-Szekeres Problem) I don't ask for detailed descriptions, although they are also welcome. You can simply give a short sketch of applications in different fields of maths or give a link. Thanks in advance!