Definitions
mdbook is a command-line tool to create books with Markdown. It is commonly used for Rust user guides, such as the Rust book and the Rust How-to book.
Markdown links and reference definitions
Markdown is a lightweight, readable markup language for writing structured documents.
A Markdown link can be an autolink, e.g. <https://example.com>, an inline link like [The user will see this](https://example.com), or a reference-style link: [The user will see this][thisisthelabel].
A reference-style link requires a reference definition with a matching label thisisthelabel: https://example.com/ on a separate line.
Images and badges
Images can be inserted using  or, reference-style, ![Image][1] followed by a reference definition [1]: <http://url/b.jpg>.
More details may be found in the CommonMark documentation.
A status badge is a small image that provides at-a-glance information, for example the build status of a code repository. Badges are commonly displayed on GitHub READMEs and inserted in mdbook documentation as links to a crate's docs.rs documentation, GitHub repo, or crates.io page. More information about badges may be found in the awesome-badges repo and in the shields.io documentation.
There is no "badge" concept in the Markdown specification. Badges are simply clickable images e.g. [  ](link-to-webpage).
Code blocks and includes
Markdown fenced code blocks (we will call them code examples as well) are inserted between two code fences (e.g. sets of triple backticks), with an optional info string (a.k.a. attributes ) after the first backtick group:
```rust
fn main() {}
```
mdbook allows including files into your book via include statements. mdbook interprets included files as Markdown. Since the include syntax is usually used for inserting code snippets and examples, it is often wrapped between two sets of backticks.
```rust
{{# include file.rs}}
```