The four main personality types, or temperaments, are sanguine, choleric, melancholic and phlegmatic. Choleric and sanguine personalities are typically more extroverted and outgoing, while melancholic and phlegmatic personalities are introverted and reserved.
Sanguine personalities are impulsive and tend to seek out pleasure and social events. People with this personality type can be forgetful and have difficulty finishing tasks.
Choleric personalities tend to be leaders and are passionate. One negative quality is a tendency for sudden depression and mood swings.
Melancholic personalities are independent and thoughtful, but they may dwell on the negative aspects of the world around them.
Phlegmatic personalities tend towards being relaxed and showing affection. They also can be lazy or passive-aggressive when dealing with issues.