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.
A corrosion resistant steel alloy. The most common stainless steel for general hardware use.
A low carbon steel for general use. Zinc plated for moderate corrosion resistance.
Solid bronze. An alloy of copper with greater strength and corrosion resistance than brass. Exact color varies.
Screws with machine threads for use with a nut or in a tapped hole.
Screws with an Allen wrench drive.