I dont think art needs to be either. There are many objects today that when first created were not meant to be art. Such as religious ceremonial objects of many cultures,today though many people consider them art because of there astetic (sic) appeal to that particular person. For alot of people though art does need to represent something for them to better understand it and if that art does represent a certain theme than the artist that created it most likelt did so intentionaly.
For me personaly art is anything that moves people on any emotional level,Happiness,sadness,anger,etc. Although if a piece of "art" does not move me in any way that certainly does not mean it is not art. So i guess to me art is anything that moves the person who created it to create it. Whether anyone else besides the artists gets anything out of it does not really matter.