Hi Hary,
Okay well if you are on a web page, you may hear Voice Over say "HTML
Content", at this point you would press Command and Option with shift
and the down arow, at which point Voice Over woul say "Interacting
with HTML Content". The Command an Option keys are commonly refered
to as the Voice over keys, many if not all of the funtions of Voice
Over are done by holding down these two keys in combination with
other keys.
Hope this helps and i hope also that this does not sound patronising
- I appoligise if it does.
Best Wishes
James