If not, don’t worry – you are in good company. The majority of people working with data have not been training in this respect: It is surprising that amongst those who establish and collect data, only rarely a statistician or data scientist can be found. We know that datasets consist of variables and observations; but it is surprisingly difficult to precisely define variables and observations in general. Tidy datasets provide a standardized way to link the structure of a dataset with its meaning; they form the basis for effective computation, modeling and visualization. In his contribution “Tidy data” Hadley Wickham, Chief Scientist at RStudio and Adjunct Professor of Statistics, explains what accounts for the quality of datasets, and how they can effectively be cleaned and prepared for analysis. This article from the Journal of Statistical Software is freely accessible.