In stead of two (or three) hihat notes per count, we also can play 4 of them. That is what we call four 16th notes. This changes the sound of the beat enormously. Maybe a little in the direction of R’n’B or soul…
This makes us count as 1e&a 2e&a 3e&a 4e&a. Yeehaa!!! 16 notes in a row.