Macintosh event -- such as a key being pressed, a mouse click,
or activity in one of the serial ports.
MIDI event -- such as a NOTE was played; a program change
was sent, etc. These correspond to one of the 8
basic MIDI "commands" as defined by the MIDI
Specification.
Isadora event -- these are events generated by one of the
buttons, sliders, dials, etc., embedded in Isadora's Control Window.
Time event -- Isadora measures time very accurately. A Time
event is one which relates to the passage of a specific length of
time.