@6f101427 yeah, I guess it's probably waste industry terminology... the machine compresses stuff (this could do cardboard, pallet wrap, anything compressible really) then you can tie straps around it to make said "bale". Thus "baler". Most industrial sites and large retail sites (i.e
 supermarkets) have one (or more), mainly for cardboard.

Basically it improves logistics efficiency by making materials more space efficient. Density is efficiency.