Emergency services have long tried to standardise which Lat/Long system to use, so that we’re all singing from the same songsheet. In the end, we discovered it’s not a biggie, because rescue helicopters can also swap systems.
Degrees and decimals might seem attractive and simple, but DMS is easily converted to actual ground measurements:
A Degree of latitude is 60NM, so a Minute is one NM and a second, as OME says, is about 30 metres.
One fact that always fascinates me is that the ancients divided the circle into 360 degrees; the French decreed the earth’s circumference to be 40,000km.
Divide 40,000 by 360 and you get 111.1111111
This is useful when converting latitude marks on a map into kilometres.