HELP WITH VPOKE,VPEEK ...

CAN SOMEONE GIVE SOME LESSONS IN USING VPEEK,VPOKE,DEFUSR,USR,POKE,PEEK COMMANDS?? IN DETAILS IF POSSIBLE

I BOUGHT ALOT OF BOOKS BUT NO ONE OF THEM HAS THE DETAILS ABOUT THESE COMMANDS..

LET THE LESSONS BE IN A NEW TOPIC ON THIS FORUM TO BE USEFUL FOR ALL MSX PROGRAMMERS..

THANKS