Well, when I was little I understood very little about the options I had when it came to believing these types of things. My family is Christian, so I just went with that for the longest time.
However, I eventually stopped believing anything in the bible because there is no actual proof of any of that. I don't believe, but I don't not believe. Meaning I do believe there's someone or something out there, but I don't think it's anything or anyone anybody could have thought up. I still do kind of believe in a God though. Being raised Christian did that, but I won't want to change that small belief I have on "God" because it's comforting to think about.
Anyways, if someone brings something religious up, I never disagree and I never agree. I just nod my head and listen, but I don't believe.