What are the various types of surge protection devices and where should they be used?

UL 1449, 3rd edition (effective September, 2009) provides following surge protector classifications:
Permanently Connected (PC)
Direct Plug-In (DPI)
Cord Connected (CC)
Type 1 – Permanently connected (PC) between service transformer and line side
Type 2 – Permanently connected on load side of service disconnect
Type 3 – Point of Use: minimum 10 meters from service panel
Type 4 – Component assemblies for SPD (surge protection device) or other non-SPD applications such as appliances
Type 5 – Discrete components for SPD or other non-SPD applications such as appliances