(see also the explanation for the main window)
This picture represents the usage of discussion forums for six courses. Each block of pixels corresponds to one hour. We can immediately see how the users of those courses used this module in different ways. Users of course 102 have done continue and uniform usage of the discussion forums. Users of course 284 have intensively used this tool either, but only on some specific periods. In particular, no discussions were made on the first and last days of the date range (which correspond respectively to the centre and the border of the spiral). We can see also that discussions were concentrated on some particular periods of time, while on course 102 they were more uniformly distributed. A different situation is for courses 66, 101, and 115, where all the accesses to Forum were made only during the latest days, while course 339 depicts an opposite situation.