Events
This counter interactively counts "events".
All it records is the time that each event occurred, in the simplest possible manner.
New events can be added by clicking on the "add event" button, or hitting any of the keys Space, Enter, Up Arrow or Right Arrow.
The most recent event may be rolled back by hitting Left Arrow or Down Arrow.
The entire event history can be deleted by hitting Escape or Backspace, or by clicking on the "clear history" button.