The greatest strength of the Markdown language is that its simplicity makes it very easy to read and write even to newcomers. This is its key design principle, as outlined by the creator of the original Markdown language.

However, this comes at a cost of customization. Many features of typical word processors are not directly available in Markdown, e.g.,

Changing the font size of a piece of text;

Changing the font color of certain words;

Specifying text alignment.

We leave it to you to decide whether such features are worth your effort. To some degree, Markdown reflects the philosophy of Stoicism: the “natural world” consists of plain text, and you should not be controlled by the desire for (visual) pleasure. Anyway, this chapter offers some tips on how you can customize the appearance and styling of elements in an R Markdown document.