Delay question

["Lee Wordsman" <lwordsman@pirnie.com>]

I recently borrowed a Digitech GSP 5 from a friend.  Last night I got a
chance to fool around with editing some of the presets.  It has 13
preprogrammed effect chains.  A couple of the chains have something 
referred
to as four tap delay where you can edit the delay time and level for each 
of
the four delays.  I'm not sure what it is that I end up hearing when this
plays.  Can anyone explain what is happening in a four tap delay.  For
example, is delay two recieving its input from delay 1 and delay 4 from
delay 3?  Any help would be appreciated.