Element of a collectionAbstract The 'Documentation Approach to Didactics' is an entry of the Encyclopedia of Mathematics Education (Trouche, Gueudet & Pepin 2018). This entry has been updated in 2020 (Trouche, Gueudet & Pepin 2020). This article is a Hungarian adaptation of this updated version. It is part of a collection, gathering such adaptations in 14 languages (https://hal.archives-ouvertes.fr/DAD-MULTILINGUAL). 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, i...