There is a little discussion here and there on the internet about if the new decade starts today or next year, 2021. Seems a bit on the silly side but it did cause me to look up the name for the numbering system that starts with zero.
It’s called zero-based numbering.
In the U.S the ground floor is the first floor but in Europe it floor zero. Starting with zero is also common in computer science.
There is a problem that has tripped me up several times with mile post markers and in other situations. From Wikipedia it turns out that it has a name. The Fencepost error or off-by one.
Counting isn’t easy. Suppose your boss wants you to work from 8am to 11am, and mop floors 8 to 11. Simple - it’s one floor per hour, right?
Nope! There are 4 floors to mop (8, 9, 10 and 11) but only 3 hours to work (8-9, 9-10, and 10-11).
Whoa – we count floors and hours differently? You bet. And somehow, if the boss said “Mop floors 8 to 11 on April 8th to 11th” everything would be ok.