Art is any human creation, which shows expression of feelings through a particular medium. Art has to have meaning and it must obtain creative and unique perception both by the artist and by the audience. For example a common criticism today of some modern painting might be, "I could have painted that", implying that the work is less worthy of the title art. Reason for this is either because the viewer fails to find the meaning in the work or because the work does not appeared to have required any kill to produce.
For something to be considered art it must have a function and a purpose. Art can inspire, beautify, inform, persuade and entertain. It can also be deceive, humiliate and anger. Art must also be allusive. Meaning that it must be able to spark our imaginations, delight our senses, lead us to think and help us develop a personal sense of beauty and truth.
Art must also be able to communicate and inform people. It must be able to arouse as ethic or moral feelings, and could be understood as a way of communicating these feelings. A good example of a good communicating art form will be performing art. There are many things today that are considered to be art based on their expression and function but personally everything cannot be considered art. Basically I think for something to be considered art it must apply to all these characteristics of art stated above and it must be a product of human creativity, created primarily as an asethic expression. Three things that I consider art are painting, performance art and sculpture. On the other hand three things I do not consider to be art are photography, graffiti and filmmaking.
Painting, performing art and sculpture are definitely considered art...