Bustince Sola, HumbertoMesiar, RadkoPereira Dimuro, GraçalizFernández Fernández, Francisco JavierBedregal, Benjamin2021-09-142022-10-2720211434-992210.1007/978-3-030-54341-9_3https://academica-e.unavarra.es/handle/2454/40492In this chapter we make a review of the notion of overlap function. Although originally developed in order to determine up to what extent a given element belongs to two sets, overlap functions have widely developed in the last years for very different problems. We recall here the motivation that led to the introduction of this new notion and we discuss further theoretical developments that have appeared to deal with other types of problems.8 p.application/pdfeng© The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2021Overlap functionsinfo:eu-repo/semantics/bookPartinfo:eu-repo/semantics/openAccess