In the
operating system for the
Apple Macintosh computer, a Desk Accessory (DA) was a piece of
software, originally written as a device driver, conforming to a particular programming model. The purpose of this model was to permit very small helper-type applications to be run concurrently with any other application on the system. This provided a small degree of
multitasking on a system that initially did not have any other multitasking ability.
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