min(2, 5) = 2
min(2, -4) = -4
max(3, 7) = 7
max(10, 0) = 10
It returns the min/max of a pair of values.
min(upperBound, max(lowerBound, value))
respectively
max(upperBound, min(lowerBound, value))
limits a value to between a lower- and upperBound (it does not change the variable, you do not pass references in wc3, but returns a new val).