Aggressive Dog - Causes and Solutions

It’s never been as common as now—the fact that dogs are attacking people, causing horrific injuries that sometimes lead to death. Is the sobriquet “dogs are man’s best friends” fair and true? Why do some dogs turn aggressive while others remain calm?
There are three undeniable facts that pertain to dogs: First, that nearly all dogs have an inherent protective instinct; Second, that though each dog is born with a definite temperament, it can be changed and molded by training and environment; Third, dog and master develop a strong bond very soon into their relationship which goes on to give the dog a sixth sense – one that includes knowing his master’s likes and dislikes.