Hound's Trail is a term used to describe the path that a hound follows when tracking an animal or person. It is made up of three components: ODOR, SPOOR, and SCENT. ODOR is the smell left behind by the animal or person being tracked, SPOOR is the physical evidence of the animal or person's presence, and SCENT is the combination of both ODOR and SPOOR. Together, these three components form the hound's trail, allowing the hound to track its target.