In his 1920s work Psychological Types, Swiss psychiatrist Carl Jung popularized the terms "introverted" and "extroverted." Introverts recharge by spending time alone and they lose energy if they're around people for long periods of time. Extroverts, on the other hand, gain energy from other people and actually exhaust themselves if they're alone. To help you fully grasp the concept, Bored Panda has compiled a list of memes that are as relevant to the subject as they're funny. And if you start nodding in approval, you're probably more of an innie. If not, you're most likely that party animal they try to avoid. But before you judge, one group or the other, remember something Jung has said, "There is no such thing as a pure introvert or extrovert. Such a person would be in the lunatic asylum." Continue scrolling, enjoy the entries and upvote your favorites.