This collaborative and interdisciplinary research project addresses a pivotal question in linguistics: what makes a variety a variety and what distinguishes it from other varieties? Specifically, it explores what makes varieties — such as dialects — coherent and distinct linguistic entities. To this end, a group of researchers from diverse disciplines and universities, specialising in various fields of linguistics, have collaborated to address this issue. The researchers involved in this project hail from a diverse range of academic backgrounds, including but not limited to the fields of computational linguistics, natural language processing and artificial intelligence research, quantitative linguistics, phonetics and speech processing, psycholinguistics, contact linguistics, dialectology, and variationist sociolinguistics. The project is being conducted in collaboration with several prestigious academic institutions, namely LMU Munich, University of Marburg, University of Tübingen, University of Bonn, Saarland University and University of Heidelberg.