topic the document will describe (e.g., `child_process`).

* Filenames should be **lowercase**.

* Some files, such as top-level markdown files, are exceptions.

* Older files may use the `.markdown` extension. These may be ported to `.md`

at will. **Prefer `.md` for all new documents.**

* Documents should be word-wrapped at 80 characters.

* The formatting described in `.editorconfig` is preferred.

* A [plugin][] is available for some editors to automatically apply these