`ref` and `relRef` look up a content page by relative path (`relref`) or logical name (`ref`) to return the permalink. Both functions require a `Page` object (usually satisfied with a "`.`"):
```
{{ relref . "about.md" }}
```
These functions are used in two of Hugo's built-in shortcodes. You can see basic usage examples of both `ref` and `relref` in the [shortcode documentation](/content-management/shortcodes/#ref-and-relref).
For an extensive explanation of how to leverage `ref` and `relref` for content management, see [Cross References](/content-management/cross-references/).
