mode menu

What is the different between norm, none or scan mode?

The following description is the difference of them.

AUTO: Always refresh waveform, synchronize when triggered.
NORM(al): Display synchronized waveform when triggered, blank if not triggering.
SING(le): Display triggered waveform and hold after triggered, blank before triggering.
SCAN: Repeatedly sweep waveform from screen left to right.
NONE: Refresh unsynchronized waveform ignoring triggering.
FIT: Automatically adjust vertical and horizontal scale to display waveform per human favor.