What is one or does it do i think my atlas lathe came with one. And my
newbie to the machining side doesnt really get the point of it currently

there is an electric motor attached ot a belt drive attached to an arbor
that ends in a small grinding attachment i assume this is essentially a
toolpost grinder?

But the application of one is still a bit of a mystery to me and i could
stand to be pointed in the right direction.
You will never have a use for it, and it will be laying around your
shop, tripping you every time you walk past it.... so, to save you all
that aggravation, you should box it up, package it well, and ship it
off to ME... and let me help you from becoming upset with it....
Ken.