Why do Religions Exist?

I think that religions exist, or still exist, because some people have a need of security. They need to have set rules and rewards (or consequenses) that tell them how to live their lives. People want to be able to have an explanation for things that may confuse or frighten them. Some religions offer people a sense of belonging, while others can give them a feeling of peace. Unfortunately, as we learn in history lessons, religion can be used as a means to control, such as in various cults, or massacre, as in the Holocaust, entire groups of people. Though religions have historically caused conflict and death, many people have religion to fill a void that otherwise would be empty.