Music
Music is all around us; it makes us who we are and it shapes our identities. When we are growing up it is a large part of how we act, who we interact with and how our social lives develop. So many different things are dependent on music. Most teenagers dress to fit in with a particular music style and we all bond with people with similar tastes. As we get older our musical tastes change, but our routes remain with us and we realise how much music has shaped who we are and where we are going.
Music also affects the way in which other art forms are identified and shaped. A movie with a techno soundtrack is going to attract a different breed of cinema goer than one with an orchestral score for example.
Without music there would be a large hole in the cultural makeup of the world. It would change the way in which everything is presented and how other art forms such as film would convey emotive scenes.
It would also change the day to day make up of our lives, with a silent gap in our day.