Why do we believe Oswald killed Kennedy?

I don’t think there will ever be a time when I stop questioning the assassination of JFK and why people think Oswald was the killer. My previous post about JFK Revealed asked a question at the end of the blog. I asked why do we believe that Oswald killed Kennedy? (http://www.andtheunderdogwins.com/jfk-revealed/ )Where is the real proof,