What do the different flight statuses mean?

Airlines and tracking systems use specific terms that can be confusing. "On time" means the flight is expected to depart or arrive within 15 minutes of schedule. "Delayed" means it's expected to be 15+ minutes late — the delay reason code may appear as weather, carrier (airline's fault), NAS (national air system/ATC), security, or late arriving aircraft.

"Boarding" means passengers are actively boarding; if it says boarding and you're not at the gate, run. "Gate closed" means the door is shut and no more passengers will be accepted, even if the plane hasn't pushed back. Most airlines close the gate 10-15 minutes before departure, and once it's closed, they will not reopen it for you regardless of circumstances.

"Cancelled" means the flight will not operate. "Diverted" means the flight landed at an airport other than its scheduled destination — usually due to weather, medical emergency, or mechanical issue at the destination. When diverted, the airline is responsible for getting you to your original destination. "In air" or "en route" means the flight is currently flying. And "arrived" typically means the plane has touched down, not that it's at the gate — taxi time from runway to gate can be 10-30 minutes at busy airports.