Friends, to me, are people you can mess with and know they know you are joking. Many of my friendships(or at least, many with other guys) revolves around I mess with you, you mess with me.

However, I believe friendship delves much deeper than that. Friends are people that you can rely on, people that will have your back, people that can cheer you up, people that will listen to you, and people that expect everything above in return.