This Dot Clock is fairly simple to read, each small dot represents a single minute and they slowly are filled up as the seconds pass by. These small (minute) dots are then grouped into large rectangles of 60 dots (or 1 hour).
So the top left group represents 00:00 - 00:59 am, the group to it's right would be 1:00 - 1:59 am and so on until the bottom right group which represents 23:00 - 23:59 pm.
Inspired by: http://www.vendian.org/envelope/dir2/day_of_dots_clock/Created By: Brett Langdon