Pinned repository
Up to six repositories a developer chooses to show at the top of their GitHub profile.
What it tells you about a developer
Pinned repositories are the developer’s own selection, which makes them the highest-information part of a profile and the first thing to read. What they chose to show says as much as the code inside it.
GitHub lists a developer’s repositories in date order, and pinning lifts a few of them to the top. The developer picks them by hand, so the pinned set is their own answer to what is worth looking at. Somebody who pins a tutorial project from four years ago has said something different from somebody who pins a tool their team uses every day.