Production
The live system real users touch. Staging is the private rehearsal copy where changes get tested first.
What it tells you about a developer
Owning code in production means a developer's mistakes had real consequences, and they built habits around that weight. Resumes blur the distinction, but a developer who has run something live can usually describe what happened the day it broke and what they changed afterward.
Teams run several copies of their software, called environments. Developers work in development, changes rehearse in staging, and users touch production. 'Broke prod' is developer shorthand for the worst-case event. The staging-then-production sequence exists so bugs get caught before customers see them.