Self defense

I'm excited! Today is my first class. I have wanted to do this for a while. I have minimal background so I'm pretty much an open slate. The place I'm going has a good mix of styles and my buddy goes there so we can train together.  I'm not looking to compete or anything, I just want the comfort of knowing I can defend myself without weapons should the need arise.  Part of me adopting the more you know the less you need philosophy.