mode

This is the name given to the value which occurs most often in a set of data.

Look at the following set of data:

2, 4, 1, 4, 3, 1, 5, 4

Rewriting these numbers in ascending order helps:

1, 1, 2, 3, 4, 4, 4, 5

We can see that 4 is the mode. This is the number with the highest frequency.