Wood screws have large threads for use in wood.
Important Note: Wood screws can be manufactured with a cut thread or a rolled thread. While the thread diameter is uniform to both manufacturing processes, the shank diameter can vary.
Flat heads are countersunk (cone shaped under the head) with a flat top. Phillips drive is x-shaped for installation with a Phillips screw driver.
Flat heads are countersunk (cone shaped under the head) with a flat top. Slotted drive has a simple slot for a flat bladed screw driver.
Screws with large threads for use in sheet metal sometimes also used in plastic, fiberglass or wood.
Screws for wood to wood fastening applications such as decks, docks and ledgers, etc.