The criticism of graffiti

If you stop to watch the walls of your city, you will see many graffitis. A lot of them would be critical with the society or with other things.
The art with spray, many times, want to show to other people the discontent they have.
The best example of this discontent is Banksy. You can see his art on the walls of London.

 



This is the art of Banksy.

But there are many other artist who want to express his discontent in walls.