ELI5 Two Factor Authentication - how are authenticator apps more secure than SMS?

How did we go from secret handshakes to digital codes? Explain “something you know, something you have, and something you are”. Where was the first computer password invented? Why are SMS codes considered not that secure? Which former CIA director had their phone compromised via a teenage phone hack? ... we explain like I'm five Thank you to the r/explainlikeimfive community and in particular the following users whose questions and comments formed the basis of this discussion: aschentei, nottherealslash, elskerelks, mazaru , dissentologist and trueeyes To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Join us on Twitter: https://www.twitter.com/eli5ThePodcast/ or send us an e-mail: [email protected]