Right-handedness

Being right-handed is the form of handedness characterized by greater coordination in the right hand and arm, and strong preference, in one-handed tasks, for using the right rather than left limb.

A variety of studies suggest that 70% to 90% of the world population are right-handed, as opposed to left-handed or having other handedness traits.

Right-hand dominance
There is no prevailing theory that explains why right-handedness is so much more common than left-handedness. Neurologically, the motor skills of the right side of the body are controlled by the left hemisphere of the brain, so researchers believe the explanation may ultimately be found in the differences between the two halves of the brain. For example, a recent study found that right-handers use the right side of the brain to focus on an entire image, but the left side of the brain to focus on details within an image. This observed difference, like many others, shows the effects of right-handedness but does not clearly indicate its cause.

Left/right-footedness and ocular dominance
Right-handed people are known to be left footed in rare occasions.

Being right-handed does not always mean that the favored foot is also on the right side. When playing soccer for instance, many people prefer using their left foot rather than the right, despite being right-handed.

People typically also have a dominant eye, a preference known as ocular dominance. There is only a weak correlation between being right-handed and left eyed.

Theories explaining right-hand dominance

 * Brain hemisphere division of labor: The premise of this theory is that since both speaking and handiwork require fine motor skills, having one hemisphere of the brain do both would be more efficient than having it divided up.

Right-handedness in society
In the past, many schools around the world forced left-handed children to write right-handed. In Hinduism, the right hand must be used for all auspicious and respectful activity, including eating, giving, receiving, and worshipful offering. In the Islamic and Arabic culture, one prefers using the left hand for tasks such as wiping oneself after using the bathroom and the right hand for eating so they can keep their level of hygiene high. Also Muslims believe that on the day of judgement your good deeds will be represented in a book and in your right hand and your bad deeds also in a book will be in your left hand, therefore whenever Muslims do something they must do it first with their right hand then their left, even with such small things as putting on a shirt, so that they are forever reminded about the day of judgment.

A very good number of technological devices are made primarily for right-handers; examples of everyday objects primarily designed for right-handers include refrigerators, scissors, microwaves, cameras, can-openers, computer mice, and padded kitchen mittens (padded on one side only). Left-handed golf clubs are more difficult to find than right-handed ones. Many classical-era Japanese swords were (and even modern cooking knives are) favored to cut more efficiently for the right-hander. Musical instruments such as guitars are also set up for right-handers, although one can usually find a similar, yet reversed shape to play left-handedly. Military rifles designed to be shot only from the right shoulder have resulted in injuries from spent cartridge casings hitting left-handers in the eye and head.

Applying more specifically to cultures where text is written left to right, writing either with a pen or a pencil in the right hand is definitely more favorable. This is because as a right handed person writes from left to right, part of the hand resting on the writing surface would be resting on plain, unused surface. In the case of left handed writers writing from left to right, their hand is much more likely to accidentally rest on the newly written text which may still be wet in the case of ink, and this would cause it to smudge and look unprofessional, and in some cases render the writing unusable and it would need to be re-written. This is one reason why right-handedness is encouraged when children learn to write.