Documentational approach to didactics
This article is an updated version of an entry of the Encyclopedia of Mathematics Education (2018) In the same time, it is the seed of the HAL collection DAD MULTILINGUAL (https:/hal.archives ouvertes.fr/DAD MULTILINGUAL) constituted by the translation of this entry in various languages. The documentational approach to didactics is a theory in mathematics education. Its first aim is to understand teachers' professional development by studying their interactions with the resources they use and design in/for their teaching. In this text we briefly describe the emergence of the approach, its theoretical sources, its main concepts and the associated methodology. We illustrate these aspects with examples from different research projects. This synthetic presentation is written for researchers, but also for non specialists (e.g. master students) interested in a first discovery of the documentational approach.