newbie

Hi

I am new to CNC machining and have been coming across term (toolings)
I don't understand such as

upshear 2 degree downshear
spiral
straight bit
compression cutter

Router vs P2P vs machining center

What is the difference between the 2? They seem to be able to do the
same job!

Also in discussions on spoilboards, "pods below holes" are mentioned.
Is pods the same as ports (holes)?


Hoping someone can provide some quick explanation and/or give links
on where on the net I can get an education on such things.

Ed