EMC and Taig w/ MicroProto and DeskCNC

I've been reading the "EMC and Taig w/ MicroProto" posts for the
past few days. The information has been very interesting. I had my
SIEG X2 milling machine converted to CNC, and after an eight month
delay I am finally going to get it running. I purchased DeskCNC
with the DeskCNC control card as my CNC interpreter. The DeskCNC
control card was built into the stepping motor controller, and I
also had Gecko stepper motor drivers added to the controller
electronics. My CAD CAM software is Virtual Sculptor 3D, from
Designs Computed, by Daniel Carr. It allows me to design, and then
generate G-code from my design. VS-3D works with DeskCNC, and most
likely with MACH 3.

From what I have learned MACH 1, 2, and 3 evolved from EMC. What is
DeskCNC based on, or what did it evolve from? Is the G-code
implementation different between MACH 3, and DeskCNC? I guess what
I am asking is what can MACH 3 do functionally different than
DeskCNC? As an example, can either software do conditional
branching? I can't think of the conventional term for this, it may
be called Parametric Programming. An application might be
engraving, where there is fixed information on each of 20 pieces to
be machined sequntially (nesting?), but on each piece there is
variable information listed in a Do Loop. Such that at the
completion of part 1, with its fixed information, the variable
information for n=1 (a person's name)would be engraved on part one.
Then a nested Do Loop would position the X, and Y axis to start the
second piece of the 20 piece run.
Then for part 2, the fixed information is repeated, and the variable
information for n=2 is engraved. In the Do Loop a subroutine might
be called to center the name about a referance X axis position.
I guess Fanuc can do Parametric Programming. Are either MACH 3, or
DeskCNC anything like Fanuc?

Also do MACH 3, and DeskCNC follow NIST RS274NGC specs for G-code?

I guess both MACH 3, and DeskCNC both do some very intricate things
with the stepping motors. Such as microstepping, acceleration
control, and particular things associated with .dxf, .igs, .stl
files that preceed the formation of G-code, and for machining
pockets, etc.

I am not trying to determine if MACH 3 is "better" than DeskCNC. I
am only trying to understand what is the functional difference
between the two interpreters. I know that there are other
interpreter software, but to keep things manageable I am only
interested in comparing MACH 3, and DeskCNC.

Can MACH 3 be used to run my stepper controller electronics with the
DeskCNC card built into the electronics?

My stepping motor electronics also have a 4th axis capability, and I
purchased a 4th axis assembly. My main applications are artistic
engraving, and jewelry. The kinds of things that artists do with
high speed hand pieces.

One reason I am asking these questions is that I would like to
convert my SIEG lathe, 14" bed, to stepping motor CNC, and I would
like to unplug my stepping motor control electronics from the mill
and plug them in to the lathe. I guess from what I've read, MACH 3
controlls lathes.
I would like to do machining on my lathe that would be done with a
form tool.

Would I have to download EMC 3, in order to run MACH 3?

If I sound like I don't know very much, your right. I'm just
getting started. Boy there's a lot to this.

Thanks in advance for your answers, help, and discussion.

Bill Perun