Application of Ramsey Numbers The definition of Ramsey numbers is the following: 

Let $R(a,b)$ be a positive number such that every graph of order at least $R(a,b)$ contains either a clique on $a$ vertices or a stable set on $b$ vertices.

I am working on some extension of Ramsey Numbers. While the study has some theoretical interest, it would be important to know the motivation of these numbers. More specifically I am wondering the (theoretical or practical) applications of Ramsey numbers. For instance, are there any solution methodology for a real life problem that uses Ramsey numbers? Or similarly, are there any proofs of some theorems based on Ramsey numbers?
Applications of Ramsey theory to CS, Gasarch