Different types of drive type screws:
- Phillips and Frearson - An X-shaped drive. Abbreviated PH.
- Slotted - A slot in the head. Abbreviated SL.
- Combination - A combination of Slotted and Phillips drives. Abbreviated combo.
- Socket, Hex or Allen - A hexagonal hole for use with an Allen wrench.
- One Way - Installs with a normal slotted driver but can not be removed without special tools.
- Square - Also known as Robertson drive. Abbreviated SQ or SD.
- Torx - A six-pointed star pattern, specifically designed to prevent cam-out and stripped heads.