The two broadest category of firearms are long guns, such as rifles or shotguns, and pistols. In order to be a competent gun owner you should know the basic types of guns and the function of each gun. You don't have to be a gunsmith to be a responsible gun owner but knowing how things works can help alleviate many headaches in the future. Plus, you don't want to look like a dumbass when it comes to your firearms. Here are some diagrams and pictures with words so you don't look like a dumbass.