# CommonMark

mkbook nominally utilizes CommonMark with some GFM extensions through the use of the comrak crate. In using comrak, a specific set of options are used, which are listed here:

    let options: ComrakOptions = ComrakOptions {
        hardbreaks: false,
        smart: true,
        github_pre_lang: false,
        default_info_string: None,
        unsafe_: true,
        ext_strikethrough: true,
        ext_tagfilter: false,
        ext_table: true,
        ext_autolink: true,
        ext_tasklist: true,
        ext_superscript: true,
        ext_header_ids: Some("header".to_owned()),
        ext_footnotes: true,
        ext_description_lists: true,
        ..ComrakOptions::default()
    };

Mostly, know that the following extensions are enabled:

- Strikethrough
- Tables
- Autolinks
- Task Lists
- Superscripts (`e = mc^2^.` → `e = mc<sup>2</sup>.`)
- Footnotes
- Description Lists:

      First term

      : Details for the **first term**

      Second term

      : Details for the **second term**

          More details in second paragraph.

Next chapter: “Syntax Highlighting”