Graffiti

 

As you can see from the picture below, it's a street art or as people call it, graffiti. Grafiti is an art that is written, painted, or drawn on a wall, usually without permission. 

But not all graffiti's illegal, sometimes there are graffiti's that's painted or drawn with permission, like some graffiti's in Montreal, Canada. They threw a Mural Festival, so artists can express their art, legally of course.

Meanwhile, the graffiti from the picture below, you can see it at Jakarta St. is painted without permission.