Working dog

A working dog is a dog that was bred or that was trained to perform specific tasks, which usually help a human. Common tasks include herding cattle, but also performing search and rescue operations, hunting, or being employed as guard dogs. Hearing dogs and guide dogs help people who are deaf or blind.

 Types of Working Dogs 

 Assistance dog are trained to help people that are disabled in many ways, some guide people with bad vision while others assist with movement.
 Detection dog or sometimes named sniffer dogs are trained to detect stuff, such as drugs, bombs, and other dangerous items.
 Guard dog are trained to guard places and livestocks.