[Elecraft] Iambic mode A vs B?

[Mike Markowski]

Can someone point me to a web page or enlighten me as to what are iambic
modes A and B, as shown on the K2 menus?  A google search brings up
keyers, but I haven't found a page with definitions yet.  Contrary to
what the K2 manual says, I find the timing on mode A to be much tighter
than mode B.  In mode A, when I try to put out a letter 'C' I more often
send either CT or K.  Mode B seems easier, probably because it has a
feel much more like the Ten Tec keyer I've been used to prior to
building my K2.  In any case I'm curious as to just what the different
modes are.

Thanks!
Mike  AB3AP