"An "executive course" or "executive golf course" is a course that's shorter than a standard golf course in one or more respects. It has a lower par because it's usually comprised of more par-3 holes than are found on a typlical golf course.
While executive courses contain more par-3 holes—and might even be made up mostly of par-3s—they can also include one or more par-4 holes and sometimes even a par-5 hole."
An 18-hole executive course is typically anywhere from a par-54 to a par-65.
An executive golf course can be a standalone operation, but many of them are part of larger golf clubs or facilities. They're included as quicker, easier options than the regulation course that's also included in the club or facility. Another place golfers sometimes find executives is as part of a practice facility accompanied by a driving range. This type of course is also sometimes called an Executive 9 or an Executive 18.
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Ref:www.thoughtco.com