Jekyll uses Markdown-formatted links, but how can I link to internal content?
[[link]]
It is now possible to link to pages other than posts using the link tag. link works for posts, pages, documents in a collection, and files.
{{ site.baseurl }}{% link _collection/name-of-document.md %}
{{ site.baseurl }}{% link _posts/2016-07-26-name-of-post.md %}
{{ site.baseurl }}{% link news/index.html %}
{{ site.baseurl }}{% link /assets/files/doc.pdf %}
Remember to include the file extension when using the link tag.
To use it to create a link:
[Link to a document]({{ site.baseurl }}{% link _collection/name-of-document.md %})
[Link to a post]({{ site.baseurl }}{% link _posts/2016-07-26-name-of-post.md %})
[Link to a page]({{ site.baseurl }}{% link news/index.html %})
[Link to a file]({{ site.baseurl }}{% link /assets/files/doc.pdf %})
See Jekyll Documentation.