Bookdown is a free and open-source R package built on top of R Markdown to make it really easy to write books and articles/reports.
The website bookdown.org is a service to host books. It is free to publish the static output files of the books, and the author retains the copyright on the books. As the site is powered by RStudio Connect, any type of content can be hosted: Books, articles, reports etc.
Interesting R books hosted on the site and accessible for free (I just mention a few):
- R Markdown: The Definitive Guide
- Geocomputation with R
- R Markdown Cookbook
- R Programming for Data Science (By Roger D. Peng)
- Blogdown: Creating Websites with R Markdown
- Efficient R programming
- Data Science at the Command Line 1e
- Statistical Inference via Data Science
- Data Science in Education Using R
- And many many others!
This site is a great and totally free resource for learning R and Data Science, the authors should be praised because the amount and the quality of content is really invaluable!