Newbie- Z Axis

[Drools]

I have a question on the placement of the Z axis on an X/Y table style Mill. On some designs the Z-Axis seems to be offset to one side while other designs it is not. Where is the optimum placement of the Z-Axis?
Also on the X/Y axis which axis is the one that moves left to right and which one moves front to back?
On a gantry style Mill which is the X and Y axis?

Thanks for the help

[ger21]

Originally Posted by Drools Where is the optimum placement of the Z-Axis? Centered between the to rails it rides on, so that there are no overhanging loads.

Originally Posted by Drools On a gantry style Mill which is the X and Y axis?

Typically the longest axis is X, so the gantry travels along the X axis, and the Y axis is the gantry itself, which the Z axis moves along on the gantry.

[Drools]

I imagine it is just a matter of opinion but is one design better than the other?
Gantry Mill vs X/Y table style?
There are probably Pro & Cons for both but does one style have more Pros than the other?
What would the largest X/Y travel be for a X/Y mill?

Thanks Gerry for the info on the axis naming conventions!