Or, put another way, do you get your energy from yourself or from other people?

Introverts are the former, extroverts are the latter — being around others for too long can drain an introvert’s social battery, whereas being alone for extended periods can make an extrovert stir-crazy. There’s a crossover, of course, with some describing themselves as ambiverts, but most of us ultimately fall under one umbrella. It isn’t always the one you’d expect: Plenty of people who seem like social butterflies are actually introverted and vice versa.