examples of heads
Head: broadened end of the screw, whose shape and slot vary.
oval head 
Slotted head topped with an ornamental spherical part that is not driven beneath the wood’s surface.
one-way head 
Slotted head having two opposing quarters removed so that the screw can be turned one way only, making it very difficult to unscrew.
socket head 
Head with a square socket that varies in size.
round head 
Slotted rounded head whose base is flat so that it presses against the wood or metal surface.
Phillips 
Head whose crisscross indentation keeps the screwdriver in the middle of the head, providing a very firm grip.
flat head 
Slotted head becoming flush with the surface of the wood when completely embedded.