While the concept of algorithms is an ancient one, the term deriving from the Persian mathematician Al Khwarizmi (780-850), algorithms have taken on a predominant role with the increasing computerization of French society. Today, algorithms are everywhere, from the construction of our news feed on social networks (with algorithms like Facebook’s EdgeRank¹) to management by algorithms (Rosenblat, 2018), via algorithmic justice² and autonomous driving. Digital players, and more specifically the GAFAMs (Google, Apple, Facebook, Amazon and Microsoft), develop numerous algorithms that ensure their financial profitability, but communicate relatively little about how they work. As a result, they remain a mystery to many, especially as they are constantly evolving to increase their performance. Indeed, most algorithms are “proprietary” (i.e. their source code is not disclosed and is protected by intellectual property laws) and kept secret. Our knowledge of them therefore comes either from ad hoc communications from companies, or from reverse-engineering work that attempts to understand the criteria taken into account by the algorithms.