An introvert and an extrovert walk into a bar. (No, this is not a joke.) It’s a Saturday night, and the place is packed. A cover band is rocking on stage, dozens of people are talking loudly over mugs ...

Those who rank high in extroversion, known as extroverts, typically focus on their external world. They tend to be more optimistic, recharge by socialising and enjoy social interaction. On the other ...