Gun dogs are classified into four major groups. There are certain people the specialize in dog training of gun dogs, so you may want to consider looking into them as well. These groups are retrievers, flushing spaniels, setters and pointing breeds. Retrievers where once known as a water spaniel. Their major role is find the shot prey and bring it back to the hunter. They are taught a command, which could be a hand, verbal or whistle. A subcategory of the retriever is a water dog. A Setter has a natural ability to find and point at prey. They have had a history as gun dogs for a long time. Flushing Spaniels are mostly used to locate and move prey out from hiding. Spaniels have also been known to have been used for hunting for hundreds of year. Pointers hunt over a larger area than the Spaniels. They are trained to locate and point out the prey, which allows the hunter to move the prey out from hiding. Gun dogs are mostly known for hunting small prey.