Do you unlock your cell phone using your fingerprint or with facial recognition? Do you shop using your bank card on the Internet or with contactless technology in stores? Do you ever wonder what it means that some messaging platforms encrypt your messages end-to-end? Information security is increasingly important in our hyper-connected lives, but we are not always aware of it nor do we know how mechanisms work that can be very convenient to use, but overwhelmingly complex to understand. "Basic Handbook of Cryptology" is an accessible volume with which to delve into the fascinating world of information encryption from the hand of the renowned cryptologist and mathematician Luis Hernandez Encinas. With an entertaining style, we will immerse ourselves in a journey through the history of cryptography: from the scytala used by the Greeks and Romans, Polybius' tablet, Alberti's disks or the various encryption methods used by kings, queens, Templars or Freemasons to keep their messages away from prying eyes, to the Enigma machine used during World War II by the Germans to send encrypted messages and deciphered by the Allies with the help of Alan Turing. And not only that, we will also delve into current security methods, such as online finance, credit card payments or cryptocurrencies and blockchain technology. An essential book for those interested in information security and its history.