My wife is a little concerned since she will have to fly by herself soon, and she just wanted to know what are the differences between the two?
- Gates are the location in an airport that allow you to both: Wait for your flight, and enter/exit the aircraft.
- Terminals are a collection of gates.
When arriving at the airport, your wife will need to locate her Terminal first, and then the gate; this is very important.
The terminals in some airports are connected - i.e., passengers can access any terminal (walk/train/shuttle) after they've been screened at any of the airport's checkpoints.
Some airport terminals are completely disconnected; this means if you need to go to Terminal B to after you've gone through security in Terminal A you will need to go tough security again in Terminal B. This is important as it could have a significant effect on her timing. So it's important to know the departure and layover airports (if any), as well as her Terminal information.
Terminals are the buildings which may have several gates. Gates are the exits from/entrances to the aircrafts.
Gates may have a direct entrance to the aircraft, or indirect (via e.g. a shuttle bus)
From a traveller's point of view, I think you can make this distinction:
- When arriving to an airport by land, you need to arrive at the right terminal (in case there's more than one). You'll enter the terminal and check in for your flight.
- Once you're in the terminal and passed check in and possibly passport control, you need to find the right gate, where you'll board your plane.