A deep link allows you to send someone to a specific part of your note.
You can create a deep link at every header:
When to use a deep link?
The deep link is designed to be shared externally (eg. in an email, in a click up task, in Slack). When you click on it, it takes you to that part of the note.
Deep links are either private (just for your team to see) or public (anyone with the link can access it, like this for example)