Trained to track and find bad guys, lost people, etc.
Patrol / Tracker Dog:
Dog is trained in handler protection. However, dog is also trained to track criminals or people that are lost.
People (only) Detector Dog:
Trained to detect people hidden in areas where they should not be located.
People Detector / Tracker or Scout Dog:
A dog designed to track criminals and to detect them or to scout for hidden people during search operations.
Tracker Dog Handler Training:
Designed to train the person on how to handle a tracking dog.