Who is Haroon Amir, Buddha of Suburbia, God, Harry from The Buddha of Suburbia and what is their importance?

Haroon is the title character of the book, though not the main character. Karim assigns him the nickname "Buddha of Suburbia" after Haroon starts giving lectures to other suburbanites about Eastern Philosophy, particularly Buddhism, in which Haroon has had a long standing interest. Karim also refers to Haroon as God.