Motor learning is a change, resulting from practice or a novel experience, in the capability for responding. It often involves improving the smoothness and accuracy of movements and is obviously necessary for complicated movements such as speaking, playing the piano, and climbing trees; but it is also important for calibrating simple movements like reflexes, as parameters of the body and environment change over time. Motor learning research often considers variables that contribute to motor program formation (i.e., underlying skilled motor behaviour), sensitivity of error-detection processes, and strength of movement schemas (see motor program). Motor learning is "relatively permanent", as the capability to respond appropriately is acquired and retained. As a result, the temporary processes that affect behaviour during practice or experience should not be considered learning, but rather transient performance effects. As such, the main components underlying the behavioural approach to motor learning are structure of practice and feedback given. The former pertains to the manipulation of timing and organization of practice (potentially for different subtasks or variations of the task) for optimal information retention (also see varied practice), while the latter pertains to the influence of feedback on the preparation, anticipation, and guidance of movement.