Story points
A relative size estimate a team assigns to a ticket, measuring complexity and uncertainty in place of hours.
What it tells you about a developer
A candidate who can explain why an estimate was wrong and what they learned demonstrates the judgment that makes estimates gradually better. Point velocities from different teams are not comparable, because the unit is local to one team.
Teams size tickets on a scale like 1, 2, 3, 5, 8 during planning. Points deliberately avoid hours, because estimating software in hours is unreliable. A team's points calibrate only against that team's own history, so point numbers carry no meaning across companies.