Generally speaking, left-handed people are those who are most comfortable and most inclined to use their left hand to write. Left-handedness isn't as simple as a physical malfunction or "just another way to be." Being left- or right-handed has to do with how the right and left sides of the brain relate to one another, and evidence supports the idea that there are clear differences between the way left-handed and right-handed people think.
According to Scientific American, about 15 percent of people are left-handed. Studies do vary on this statistic, partly because the number of left-handed people varies from culture to culture, and partly because of the lack of a true definition of left-handedness. Some scientists consider those who use their left hand to write but their right side for everything else--their right eye to look through a camera lens and their right foot to kick a ball, for example--to be left-handed, while others don't.
Causes of Left-Handedness
The reasons why some people are left-handed are not entirely clear, but they seem to depend on a mixture of genetic and environmental factors. Left-handedness does seem to run in families, but it also appears in families where no immediate member is left-handed. Some theoretical environmental reasons for left-handedness are birth trauma, exposure to high levels of testosterone in the womb and physical conditioning.
In spite of a long-standing belief, left-handed people are not any clumsier than right-handed people. They do have trouble manipulating items that are made for right-handed use, such as can openers or scissors, but they actually manage better than right-handed people who attempt to use similar items made for left-handed people. Also, left-handed people do not die disproportionately sooner than right-handed people. This idea came out of a 1991 study that has since been discredited.
Advantages of Right-Handed People
The most obvious advantage to being right-handed is that most items--from door handles to drinking fountains--are geared toward righties. Additionally, right-handed people have never had to deal with the social stigma commonly attached to being left-handed, although this negative perception has diminished greatly in modern times.
Advantages of Left-Handed People
Lefties do have some significant advantages over right-handed people. They tend to be more athletically inclined, to have more spatial awareness and to think more quickly. According to a study by Dr. Alan Searleman of St. Lawrence University in New York, "true" left-handed people--those who favor their whole left side for physical activities--have twice the problem-solving skills and a higher I.Q. than right-handed people. People who use their left hand to write but favor their right side in everything else scored the same as "true" right-handed people.
Famous Left-Handed People
Some famous left-handed people include: Presidents George H.W. Bush, Bill Clinton and Barack Obama; Prince Charles and Prince William of England; musicians Jimi Hendrix, Kurt Cobain and Paul McCartney; scientists Isaac Newton, Marie Curie and Benjamin Franklin; artists Michelangelo and Leonardo Da Vinci; and historical figures Alexander the Great, Charlemagne and Julius Ceasar.