The accuracy, precision and economy of performance of a specific movement pattern relative to a particular task. A well-established classification for such movement patterns is that between open and closed skills, first introduced by E. Christopher Poulton in his monograph Anticipation open and closed sensorimotor skills. Cambridge: Medical Research Council, 1950. It was later applied to sports situations by Barbara Knapp in her book Skill in sport: the attainment of proficiency. London: Routledge & Kegan Paul, 1967. A closed skill is an action with a clear beginning and end in which the environmental context is relatively stable and predictable, and thus the action shows little change from trial to trial. Examples include a penalty shot in basketball and the action of a shot-put. An open skill in performed in a constantly changing environment that requires the action to be continually adjusted. Examples include a pass in basketball, hockey or soccer. In essence, the distinction is a continuum concerned with environmental effects on performance. Then there is the one-dimension versus the more complex two-dimension taxonomy of motor skills devised by Antoinette Gentile in her paper A working model of skill acquisition with application to teaching. Quest, 1972, 17, 3-23. The former is the closed-open skills continuum of these two extremes or that of discrete (e.g., punch in boxing) to continuous (e.g., walking) actions. The two-dimensions refers to the function of an action and whether it requires two things (e.g., manipulating an object and moving the position of the body. Given that skill acquisition involves a long process of learning, it not appropriate to apply it to the movements and actions of young infants. The term (motor) ability is more appropriate in this instance.
See Action, Baldwin effect, Fine motor abilities, Fundamental movement patterns, Gross motor abilities, Motor ability, Motor development, Motor milestone, Movement, Movement coordination, Pattern, Perception-action coupling, Skill (general)