Handedness is a better (faster or more precise) performance or individual preference for use of a hand. Handedness is not a discrete variable (right or left), but a continuous one that can be expressed at levels between strong left and strong right.

While in an ordinary disclosure the terms left and right are used to define handedness, there are actually four types: left-handedness, right-handedness, mixed-handedness, and ambidexterity. Left-handedness is somewhat more common among men than among women.
Left-handedness is less common than right-handedness. Left-handed people are more skillful with their left hands when performing tasks. Studies suggest that approximately 10% of the world population is left-handed.

being left-handed

social stigma

Many tools and procedures are designed to facilitate use by right-handed people, often without even realizing difficulties placed on the left-handed. "For centuries, left-handers have suffered unfair discrimination in a world designed for right-handers." Moreover, as well as inconvenience, left-handed people have been considered unlucky or even malicious for their difference by the right-handed majority.

In many European languages, including English, the word for the direction "right" also means "correct" or "proper". Throughout history, being left-handed was considered negative. The Latin adjective sinister means "left" as well as "unlucky", and this double meaning survives in European derivatives of Latin, including the English word "sinister" (only when referring to the viewer's left of a coat of arms).

There are many negative connotations associated with the phrase "left-handed": clumsy, awkward, unlucky, insincere, sinister, malicious, and so on. A "left-handed compliment" is considered one that is unflattering or dismissive in meaning. In French, gauche means both "left" and "awkward" or "clumsy", while droit(e) (cognate to English direct and related to "adroit") means both "right" and "straight", as well as "law" and the legal sense of "right". The name "Dexter" derives from the Latin for "right", as does the word "dexterity" meaning manual skill. As these are all very old words, they would tend to support theories indicating that the predominance of right-handedness is an extremely old phenomenon.

Black magic is sometimes referred to as the "left-hand path".

Until very recently in Taiwan (and still in Mainland China), left-handed people were strongly encouraged to switch to being right-handed, or at least switch to writing with the right hand. Due to the importance of stroke order, developed for the comfortable use of right-handed people, it is considered more difficult to write legible Chinese characters with the left hand than it is to write Latin letters, though difficulty is subjective and depends on the writer. Because writing when moving one's hand away from its side towards the other side of the body can cause smudging if the outward side of the hand is allowed to drag across the writing, writing in the Latin alphabet might possibly be less feasible with the left hand than the right under certain circumstances. Conversely, right-to-left alphabets, such as the Arabic and Hebrew, are generally considered easier to write with the left hand in general.[citation needed] Depending on the position and inclination of the writing paper, and the writing method, the left-handed writer can write as neatly and efficiently or as messily and slowly as right-handed writers. Usually the left- handed child needs to be taught how to write correctly with the left hand, since discovering a comfortable left-handed writing method on one's own may not be straightforward.

international left-handers day

International Left-Handers Day is held annually every August 13. It was founded by the Left-Handers Club in 1992, with the club itself having been founded in 1990. International Left-Handers Day is, according to the club, "an annual event when left-handers everywhere can celebrate their sinistrality [meaning left-handedness] and increase public awareness of the advantages and disadvantages of being left-handed." Again according to the club, "in the U.K. alone there were over 20 regional events to mark the day in 2001- including left-v-right sports matches, a left-handed tea party, pubs using left-handed corkscrews where patrons drank and played pub games with the left hand only, and nationwide 'Lefty Zones' where left-handers creativity, adaptability and sporting prowess were celebrated, whilst right- handers were encouraged to try out everyday left-handed objects to see just how awkward it can feel using the wrong equipment!"

source: wikipedia