Treballs Finals de Grau de Matemàtiques, Facultat de Matemàtiques, Universitat de Barcelona, Any: 2018, Director: Carlos Dorce[en] In this work we give an analysis of how Blaise de Vigenère described the cipher that has been attributed to him. For that purpose, we study directly from the Traicté des Chiffres. We also explain the context of his work and show the evolution of cryptology as to understand how the autor came up with his cipher.