Functional wiki:
ly, functional' refers to something with and able to fulfill its purpose or function.''In mathematics and computer science, the term functional is a term applied to certain functions.In computer science, it can refer to functional programming.In design, functional form.In medicine, the term functional is sometimes used to describe symptoms that have no organic basis, e.g. if they are a result of psychological or perceptual dysfunction.''In music, diatonic functionality.
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