While shopping for screws to mount hooks on the deck rail for wet bathing suits at the Wisconsin lake house, I came across these drawers in the hardware aisle. Could there really be, in the land of dairy where locals are affectionately referred to as 'cheeseheads', such a thing as cheese head screws?
Turns out, information courtesy of several online encyclopedias and hardware description sites, that screws can be classified by their screw portion and by their head portion. A "wood" screw had a portion of the shaft near the head that is free from threads. The idea is that when attaching a piece of wood to another, the threaded portion will bite into the wood below and but not into the thing being attached. The thing being attached to the wood will merely be pulled into it tighter, rather than the screw being pulled deeper into that thing being attached. A "machine" or a "sheet metal" screw has threads all the way along it, because it holding stiffer parts to each other that can be held in position more accurately prior to beginning screwing.
The heads are named for their profile shape. A head that tapers down into the object is called 'flat' because it ends up flush with the surface when screwed in. There are a number of names for screws that stay above the surface, such as dome, round, pan, and button, that describe the profile of the shape that stays above the surface. An 'oval' screw is not quite accurately named, but has a part of the head that is sunk below the surface and a bit that domes up above the surface to catch the screw driver. A cheese head screw is a special form of the raised head. The head is cylindrical and deep, like a teeny tiny wheel of cheese there on the surface, according to definitions I found, though the pictures on these drawers, taken with my phone, seem to show them with rounded edges and not all that deep. At any rate, cheese head screws is a name that makes me chuckle.