Base-12 is a positional number system of counting based on the number cycle from 0 to 11.
Also, called the duodecimal or dozenal system, base-12 has been around for ages but has been all but replaced in modern times by the base-10 or decimal system which counts in cycles of ten, from 0 to 9.
However, we still use base-12 (and its big brother base-60) in a few notable areas such as measuring time in months, hours, minutes and seconds, rotational angles in degrees, geographic/GPS coordinates in degrees, minutes and seconds and, of course, beer and doughnuts by the delectable dozen.
Although having ten fingers may make it easier to count in base-10, base-12 is hands-down better for a number of reasons:
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For a quick overview of Base-12 and why it's better than base-10, check out my article: How Base-12 Numerology Unlocks the Universal Wisdom of Twelve