that's just de-spruing.
you may have noticed the material itself is very much the same consistency as chalk, just a but less dusty when it comes to handling the units in your fingers.
CAM is just Computer Aided Manufacturing - which literally means as it says, using a computer to guide cutting tools or extrusion tools to manufacture an object. this is not native to dental by any stretch of the imagination.
some years ago the invention of the milling machine and the lathe for metalworking spurred a huge surge in trades and apprenticeships as people acquired the skills to use these analog devices to revolutionize our way of life - making things like steel doorknobs, windowframes, aluminum bits of aircrafts, missiles, shoes, and then re-inventing industry by making the machines themselves with new space age technology hydraulics and pneumatics became actuators for the stamping process, to literally push out thousands more items at greatly reduced prices, completely turning around the way we now see modern life.
the most recent invention that revolutionized that revolution, was automating the milling and lathing via computerized numerical control (cnc) systems. you could just press a button and make your mill move through a series of points automatically, without the need of manually turning the dials and gears to get the right positions.
in the 80's cnc technology for industrial uses reached a sort of limit, be machines got to be very very large and very very heavy and very very sophisticated - so much in fact, that new ways of designing parts opened up. later in the 80's two things happened, the invention of the computer aided 3d design program, and the first 3d printing systems began to be born. by far the design software was the more widely adopted - it led its own field of trades for 20 more years, as defence agencies and intelligence agencies worked in the same field of I.T. both spying and attempting to halt things like people designing harrier jets in their basements. it was a real fear. it was not unheard of, as kids in the 90's with their nintendos and sega genesises nurtured a love of the digital arts, saw major advances in computer technology every year. more power for designing means more fuel for the cnc world.
but then something a bit interesting happened.
as those mega cnc's of the early 90's became too lumbering to efficiently move from A to B, a mathematical idea was hatched, to convert those nanoscale move commands (yes, some machines were able to read and execute commands down to .25um (one quarter of one micron) ) into an efficient curve instead. moving along the curve would prove much easier on both the design and the manufacturing and would vastly reduce file size (memory was a big thing back then) and computation times, and even reduce the requirements on the size of the machine required to make any object.
this new, wild spline idea was called NURBS, and its impact on dental is still being seen; NURBS conversions at the cnc enables higher accuracy, smoother finishes, and causes less internal vibration of the machine because it eliminates (or reduces greatly) the jerky motions of immediate changes in direction.
NURBS is still a thing that really is made for much bigger machines and very prevalent on japanese technology more than german.
NURBS is a thing now embedded into many CAD programs as a method of creating surfaces based on lines that never cross each other. its pretty well the foundation of solidworks.
anyway all that to say theres a lot to know in the world of CAM, so it would be helpful to figure out in which aspect you want to get better - and how you want to grow as a human. or martian, i don't judge.
chalky works for me too, Check youtube for some tutorial also to gain more info
