left-handedness

Left-handedness refers to the habitual use of the left hand over the right for activities. This is a visible aspect of laterality, which describes how different functions are specialized in each hemisphere of the brain or side of the body. While most people are right-handed, a smaller percentage are left-handed, and some are ambidextrous, able to use both hands with equal ease.123

The exact origin of handedness is debated, with theories suggesting genetic inheritance, environmental influences, or a combination of both. Research indicates a tendency for fetuses to show larger fingerprints on the right hand, and most babies naturally favor one arm, often the right. Despite this, handedness can shift during infancy, and consistency in hand preference generally increases with age. The brain's left hemisphere is often associated with language functions, and this hemisphere typically controls the dominant (usually right) hand.23