The science of happiness has been booming lately, and we've found out a lot about who's happy, what makes us happy and how to become happy. Take this quiz to find out how much you know about the art of being happy.
Even though 48 percent of marriages end in divorce these days, marriage is still the best gauge of happiness.
The survey showed that women had greater overall happiness, especially in Japan, Pakistan and Argentina.
Sorry, ladies -- that happiness apparently isn't going to last. A study by the Journal of Happiness Studies found that men get happier as they get older and women get unhappier.
Positive psychology studies various aspects of happiness -- like the difference between momentary elation and enduring happiness.
Denmark wins out in this study, in which people were quizzed on their happiness levels.
The tiny Pacific island of Vanuatu wins, which shows that big carbon footprints don't necessarily equal big happiness.
Exercise lowers cortisol levels, which can help you de-stress and, hopefully, make you feel a little happier.
Endorphins it is. If you're looking for an endorphin rush, you're most likely to get one after intense aerobic activity.
In the 1970s, Economist Richard Easterlin found that poor people became happier with increased income. However, it was true only up to a point.
After individual income had increased to a certain level, happiness became tied to relative income -- their income as compared to that of their peers.
A 2004 study found that happy people tended to make prejudicial evaluations of other people. No one's sure exactly why, but it could be because happier people aren't motivated to think analytically and so naturally resort to stereotypes.
Thomas Jefferson penned this famous phrase in the Declaration of Independence.
Hmmâ€¦we were surprised by this one, too -- but according to the studies, having children does not increase a person's happiness.
Even though women and African-Americans have made great social strides in recent decades, they've apparently been becoming unhappier.
Eating chocolate, having sex and hearing happy music all cause the release of dopamine.
Surprise, surprise -- the tropical paradise of Hawaii is the happiest state in the country.
Vermont was the sole representative of the East -- the rest of the top 10 were in the West and Midwest.
Music therapy has been shown to be the most effective type for sick kids. It's also very helpful in patients with depression.
Most people don't need scientific research to tell them this, but it's true: Study after study has found that pets make us happy.
According to a study published in "The Gerontologist," happy men lived 16 years longer and happy women lived 23 years longer than their unhappy counterparts.