Linear terminals
A single long building with gates along one or both sides. Easy to understand, but walking distances can be long end to end. What you see from security is usually most of what there is.
Pier (finger) terminals
A central hub building branches into one or more narrow piers lined with gates. Efficient for airport design, but easy to walk the wrong pier entirely if you are not watching gate numbers closely.
Satellite terminals
Separate gate buildings connected to the main terminal by tunnel, train, or shuttle rather than a direct walk. These are the layouts most likely to catch an unprepared traveler off guard, since reaching a gate can require a transit ride, not just a walk.
Questions people ask
How do I know which terminal type I am in?
Terminal maps posted near security and at major junctions usually show the overall shape; satellite terminals are the easiest to spot because they explicitly mark a train or shuttle connection.
Which layout is fastest for a tight connection?
Linear and single-pier layouts are generally fastest since they rarely require a transit ride between gates, unlike satellite designs.