What is the best way to know the xyz in zbrush while working thanks .
Check out the practical guide for more understanding.
i think it would help you.
http://www.zbrushcentral.com/zbc/showthread.php?t=3471
With an 3D object
Menu Transform / Info will give you XYZ
With a brush
For the Z you can use menu Picker Sub menu Z depth / Click and drag on
For the X Y Menu Preference Utilities :)+
Have fun Zbrushing! 
Pilou
thank you verymuch i think i got it
http://www.zbrushcentral.com/zbc/showthread.php?t=27260
But this is the wrong forum for it… There is a forum for Questions.
LemonNado
Just take a look at the Tools–>Preview window… X goes to the right Y to the top and Z into your monitor - always!