K-9 units are specialized teams in law enforcement that use trained dogs to assist in various tasks. These dogs, often referred to as K-9s, are trained to detect drugs, explosives, and even locate missing persons. The bond between the dog and its handler is crucial, as they work together to perform their duties effectively. K-9 units can be found in police departments, military operations, and search-and-rescue missions. The dogs used in these units are typically breeds like German Shepherds, Belgian Malinois, or Labrador Retrievers, known for their intelligence and strong sense of smell. Their training involves rigorous exercises to ensure they can perform under pressure.