The high temperatures in a very cold town in Canada over one week were
-20, 0, -5, 0, 0, 1, 0.
What is the mode of the temperatures?
Since 0 occurs more than any other number in the list, 0 is the mode. Boy, we bet people were sweatin' on that 1-degree day.
It's possible for a list of values to have multiple modes, or no modes at all.