The Schwarz lemma is considered to be one of the most elementary and beautiful properties of the holomorphic functions between unitary discs in the complex plane. To prove it one only needs to be familiar with the basic properties of holomorphic functions. It gives us an answer to a most short and simple question, namely how large can a derivative of such a function be at the origin. At the same time this simple lemma happens to bring up many intricate questions about possible generalizations, applications in other fields, and finally about its origin. In this diploma we endeavour to extend its scope and try to approach the case of the name of the rose.
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