constructs a numeric row array by specifying a starting value, an increment value, and a terminating value, with those values separated by colons.
The array's first element is the starting value, second element is the starting value plus the increment value, and so on, until the terminating value is reached
A negative increment (or decrement) value used in the colon operator constructs an array with elements in descending order
(If the increment value is 1, the increment value can be omitted from the colon operator. Good practice is to omit the increment value in the colon operator if the increment is 1.)
(Starting value can't be greater than ending value when using increments)
Ex: myArray = [5:1:9] yields array [5, 6, 7, 8, 9].