[CornCobs]

Seconded. I was taught ggplot by a great stats professor and the framing of visualizations as a language (gg actually stands for the grammar of graphics!) describing the relation between data and visual elements (layers in the graph) really made something click.

The amount of consideration and careful design behind tidyverse APIs (tidyr, ggplot, dplyr) really astounds me. I've never felt the need to actually memorize any of them but they come to me so naturally whenever I type "library(tidyverse)". Very few DSLs, libraries or APIs have ever made me feel this way, and certainly NOT Python and the mess that pandas/matplotlib/scikit is. Even more impressive that he managed to build such a consistent layer atop the hack that is base R.

Note that I've nothing against base R. It really appeals to the hacker in me and it certainly has a ton of cool features (a condition system, multiple function evaluation forms - in what other language are `if`, `while`, `repeat` and even parentheses `(` and the BLOCK STATEMENT `{` all implemented as functions?) but damn if it isn't a mess of corner cases and gotchas.