The geniuses at RStudio have a super-sweet set of cheat sheets for:

1. Shiny
   • to build fully dynamic/interactive web apps, including interactive statistical models and output graphics.
2. Data Visualisation
   • Explaining the super sweet ggplot2 package.  ggplot2 can be a bit hard to understand at first, but this will definitely get you started.
3. Data Wrangling
   • The dplyr and tidyr packages are must haves whenever you need to either reshape, transform or combine data sets.  Think “split-apply-combine”: split the data, apply a function, then combine it back together, all at once, its GOLD.
4. Sharing R Packages
   • Once you’ve got a handle on R, you might want to create your own packages, this one will get you on the way.
5. R Markdown & Reference
   • R Markdown lets you create documents. Basically you write some code in R and export the results as html, pdf, or MS Word files.

All of the cheat sheets are on the RStudio website:

https://www.rstudio.com/resources/cheatsheets/