Introverts (or those of us with introverted tendencies) tend to recharge by spending time alone. They lose energy from being around people for long periods of time, particularly large crowds.
Extroverts, on the other hand, gain energy from other people. Extroverts actually find their energy is sapped when they spend too much time alone. They recharge by being social.
Are you an introvert or an extrovert? And what does it mean for your career?