Of course, such classifications are hardly concrete. Graffiti varies as much as the people who create it. For example, while it is easy to find bland and uninspired graffiti on a huge scale on a warehouse wall, it is also quite possible to find excellent works of art adorning the likes of a paper towel dispenser.

Could it be called tragic that all graffiti, regardless of quality or content or location, is judged equally negative and equally illegal?

Modern graffiti is fairly widespread and diverse. While most are willing to categorize it according to the location at which it appears, it is important to note that the graffitic content also has considerable variation.

Graffiti tends to pop up just about anywhere. Common city locations include the walls of downtown buildings, dumpsters, fences, on and under bridges, on the sides of train cars, buses, subways, and many other places. Rural graffiti is less common but can also be found on train cars and bridges. Interior graffiti is common on lockers, backroom walls, and bathroom walls and stalls. A good rule of thumb is that the likelihood of the presence of graffiti increases the more public and less maintained a location is.

The most recognizable form of graffiti is a tag or one of its more highly developed forms. This consists of a name or nickname or other identifier that is spray-painted on a surface in a decorative form. Tags, murals, and other large forms of graffiti often overshadow less artistic and smaller forms. Common to the bathroom stall, etc. is the "wuz here" identifier, the humorous or profane (or often both) sketch, the complex illustration, the political comment, the poem, the comment, the "dirty" comment, the joke, telephone numbers, and the like.