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Together, tidying and transforming are called wrangling
Hadley Wickham • R for Data Science: Import, Tidy, Transform, Visualize, and Model Data
R for Data Science: Import, Tidy, Transform, Visualize, and Model Data
Hadley Wickham, Garrett Grolemund
amazon.com

In brief, when your data is tidy, each column is a variable, and each row is an observation.
Hadley Wickham • R for Data Science: Import, Tidy, Transform, Visualize, and Model Data

nonnegotiable.
DJ Patil • Ethics and Data Science
Visualizing {dplyr}’s mutate(), summarize(), group_by(), and ungroup() with animations | Andrew Heiss
Andrew Heissandrewheiss.com