Each record has an _id. This ID is basically a form of the filename. Depending on if you are looking at an attachment or a page the rules are slightly different.

For pages the ID is the name of the folder. So if you have a page called docs/overview/contents.lr then _id is overview. If you have however an attachment named docs/overview/screenshot.jpg the _id will be the filename of the attachment: screenshot.jpg.

Note that IDs are not globally unique! There is also the _path which is the entire path if the record.

The _id is automatically set and cannot be overridden.


<ul class="nav">
{% for item in site.query('/projects') %}
  <li{% if item._id == this._id %} class="active"{%
    endif %}>{{ item.name }}</li>
{% endfor %}