What is numpad Commander?

[Chris Gilland Desktop]

My subject preetty well says my question, but, what is num pad commander? 
If I hit vo+the key right above the 7 key on my numpad, it says num pad 
commander on, then again turns it back off.  Does this make it where I can 
use keys on the numpad to control voice over?  If so, where can I find a 
listing of these commands as with it on, vo+4, 6, 8, and 2, don't seem to be 
doing the same as vo up, down, left, and right.  So, my guess is, the 
commands over there are a little different, if not, quite! different.

Chris.