1. Button Head Screws: These screws have a low-profile, rounded head with a socket recess. They are commonly used in applications where a smooth, flush finish is desired.

2. Socket Set Screws: These screws have a fully threaded body and a socket recess at one end. They are typically used to secure one object within another, often in mechanical or industrial applications.

3. Flat Head Screws: Also known as countersunk screws, these have a flat head that sits flush with the surface when installed. They are commonly used when a smooth, finished appearance is desired or when the screw head should not protrude.

4. Shoulder Screws: These screws have a cylindrical shoulder between the head and the threaded portion. They are often used as pivot points or precision locating components in machinery and equipment.

5. Socket Cap Screws: These screws have a cylindrical head with a socket recess. They are commonly used in applications where a high-strength fastener is required, such as in automotive, aerospace, or machinery industries.

6. Socket Shoulder Screws: Similar to shoulder screws, but with a socket recess in the head. They are often used for precision applications where a tight tolerance fit is required.