The AR-15 is a selective-fire, gas-operated rifle primarily utilized by the U.S. military. It was first designed in 1956 by Eugene Stoner and L. James Sullivan. Although perceived to be an "assault rifle" the ArmaLite AR-15 is not. It is now, in its much more advanced stage, standard issue for the military and commonly used by civilians for shooting sports and self defense.
The AR-15 directly impacts our society. In the most obvious way, as I stated previously, it is part of our national and internal defense, being that the rifle is standard issue for the U.S. military. It is also available for purchase to the public (if you can afford it). Although much about the AR-15 has been negatively displayed in the news, I think responsible citizens who are trained can use it in self defense and in defense of others.
In an article by Dallas News, four citizens explain why they own an AR-15: http://interactives.dallasnews.com/2016/gun-owners/
Obviously, there are issues with this kind of technology. According to an article by NBC News, a man in Oklahoma used an AR-15 to kill three teen home intruders: http://www.nbcnews.com/news/us-news/oklahoma-man-uses-ar-15-kill-three-teen-home-intruders-n739541. The AR-15 doesn't exactly proclaim peace or benefit those it's used upon. Should citizens be allowed to own one? The AR-15 presents a variety of legal issues and questions that have been debated by the people and leaders of the U.S. government. But I think it's incredibly useful for protection: for our country and for our homes.