The ancient Greeks, Babylonians and Assyrians were the first cultures to use dogs as a form of protection. From then on humans have bred dogs specifically as guard dogs. In 1899 German Shepherds were named the original "watch dogs" and have held the title into today. Around the beginning of the 20th century, this breed began to be employed by police departments and the military.

So how effective are these guard dogs anyway? Well they can actual provide a strong defense even without attacking. It has been reported that 65% of convicted criminals confirmed that the presence of a large and intimidating animal would be enough to scare them off. This proves that having a well-trained guard dog can provide your home with an extra line of defense.

There is not just one classification of "guard dog," so it is important to assess your needs when picking the right pooch. There are watch dogs, guard dogs, protection dogs and livestock guard dogs. Guard dog breeds are trained to pin down any perceived threat when commanded. These dogs can apply up to 750 pounds of pressure into a single bite and tear through both muscles and tendons - which has earned them the other title of “Kill Dogs.” While aggressive to strangers they are gentle and loving towards their families. These breeds include: Doberman Pinscher, German Shepherd, Rottweiler, and American Pit Bull Terrier.

Unlike guard dogs, watch dogs are not trained to attack intruders but rather alert their owners of any unfamiliar presence that is spotted on their property. Even without attacking they are intimidating, as their warnings can include terrifying snarls. These dogs are good for families due to their non-aggressive nature. Watch dog breeds include: Cairn Terrier, Akita, Schipperke, Miniature Pinscher and Airedale Terrier.

Protection dogs and livestock guard dogs are breeds that possess combined traits of the other forms. Protection dogs are a mix of a watch dog and guard dogs. They can be trained to attack intruders, however it does not come as naturally to them. Protection dog breeds include: Great Dane and Giant Schnauzer.

Livestock guard dogs on the other hand can be trained to perform the duties of all three of the other classifications. These dogs are alert, attentive and intelligent and thrive in rural areas. Livestock guard dog breeds include: Anatolian Shepherd, Estrela Mountain Dog, and Komondor.