The terms "task tracker" and "job tracker" are both used in the workplace. Could you perhaps give a brief explanation of how these two systems work?

For this system: Airline Reservation System For Customers Book Flights Buy Tickets Make Payment Print Boarding card Cancel booking For management staff Create new Flights Modify Flights Details Flights cancel .... Write one scenario and design the corresponding Sequence Diagram that describe one of the main use cases.

Is there a specific instance you're thinking about that fits within a working context?