The BFI is designed to measure the Big Five personality dimensions.
Extraversion is associated with warmth, gregariousness, assertiveness, and excitement seeking.
People high in Extraversion enjoy meeting new people and tend to maintain a fairly stable, positive mood under most circumstances. The opposite of Extraversion is introversion. High scorers tend to be sociable, friendly, fun loving, talkative Low scorers tend to be introverted, reserved, inhibited, quiet. It implies a concern for the welfare of other people, closely related to the idea of social interest. People high in agreeableness generally trust other people and expect other people to trust them.