We can make a distinction between the purposes of art (that is: what art aims to accomplish) and art's functions (what art achieves). 
 
There are five broad functions of art: 
 
A) Aesthetic, Expressive, Social, Ritual, Political 
B) Decorative, Commercial, Personal, Spiritual, Historical 
C) Symbolic, Therapeutic, Educational, Reflective, Entertainment 
D) Abstract, Realistic, Surreal, Minimalist, Impressionist