A link is a clickable part of a page that takes you to information somewhere else. That place might be another page, a file, or a section lower down on the same page. A link is like a signpost: it points you toward a destination.
For example, selecting “Read the privacy policy” should open the policy, not submit a form or change a setting. This is why links and buttons have different jobs: links move you to a place, while buttons carry out an action.
Good link words tell people where they will go. “Download the guide” is clearer than “Click here,” because the destination is understandable even when someone sees the link by itself.