Your personality influences everything from the friends you choose to the  candidates you vote for in a political election. Yet many people never really spend much time thinking about their personality traits.

Understanding your personality can give you insight into your strengths and weaknesses. It can also help you gain insight into how others see you.

Most modern-day psychologists agree there are five major personality types. Referred to as the "five factor model," everyone possesses some degree of each.

1. Conscientiousness.

People who rank highest in conscientiousness are efficient, well-organized, dependable, and self-sufficient. They prefer to plan things in advance and aim for high achievement. People who rank lower in conscientiousness may view those with this personality trait as stubborn and obsessive.

Fun fact: Studies show marrying someone high in conscientiousness increases your chances of workplace success. A conscientious spouse can boost your productivity and help you achieve the most.

2. Extroversion.

People who rank high in extroversion gain energy from social activity. They're talkative and outgoing and they're comfortable in the spotlight. Others may view them as domineering and attention-seeking.

Fun fact: Be on the lookout for a strong handshake. Studies show men with the strongest handgrips are most likely to rank high in extroversion and least likely to be neurotic. That doesn't hold true for women, however.

3. Agreeableness.

Those who rank high in agreeableness are trustworthy, kind, and affectionate toward others. They're known for their pro-social behavior and they're often committed to volunteer work and altruistic activities. Other people may view them as naïve and overly passive.

Fun fact: Seek a financial investor who is high in agreeableness. Studies show agreeable investors are least likely to lose money from risky trading. Avoid an investor high in openness--that personality is associated with overconfidence that can lead an investor to take excessive risks.

4. Openness to Experience.

People who rate high in openness are known for their broad range of interests and vivid imaginations. They're curious and creative and they usually prefer variety over rigid routines. They're known for their pursuits of self-actualization through intense, euphoric experiences like meditative retreats or living abroad. Others may view them as unpredictable and unfocused.

Fun fact: Openness is the only personality trait that consistently predicts political orientation. Studies show people high in openness are more likely to endorse liberalism and they're also more likely to express their political beliefs.

5. Neuroticism.

Neurotic people experience a high degree of emotional instability. They're more likely to be reactive and excitable and they report higher degrees of unpleasant emotions like anxiety and irritability. Other people may view them as unstable and insecure.

Fun fact: Neurotic people seek acceptance by publishing a lot of pictures on Facebook. Studies find they're less likely to post comments or updates that could be seen as controversial, and much more likely to post lots of pictures (they also have the most photos per album).

Understanding the basics of personality.

Personality remains relatively stable over time. The personality traits you exhibited at age 7 are likely to predict much of your behavior as an adult.

Of course, you can change some of your personality traits. It takes hard work and effort to make big changes, but most scientists agree that it is possible.