Conditional operator ( ? ).
The conditional operator evaluates an expression and returns a different value according to the evaluated expression, depending on whether it is true or false. Its format is:
condition ? result1 : result2
if condition is true the expression will return result1, if not it will return result2.
7==5 ? 4 : 3 returns 3 since 7 is not equal to 5.
7==5+2 ? 4 : 3 returns 4 since 7 is equal to 5+2.
5>3 ? a : b returns a, since 5 is greater than 3.
a>b ? a : b returns the greater one, a or b.