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&lt;iframe src="https://skeleton-bookdown.netlify.com/" width="100%" height="500px"&gt;&lt;/iframe&gt;

https://skeleton-bookdown.netlify.com/

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The index.Rmd contains the first "chapter" because it starts with a level one header. Notice that in your rendered book, the second chapter is called "Introduction"- but the filename was 01-intro.Rmd. Prerequisites, which is the first level-one heading in the index.Rmd became Chapter 1. And Introduction became Chapter 2.

I'll show you later how to c