Have you ever seen graffiti on walls, buildings or trains? Some people believe it is an art form, while others believe it is a crime. As with many complex issues, the truth is somewhere in between the two extremes.

Graffiti refers to images or words scratched or painted on property. Graffiti includes any type of public markings and can be as simple as written words or as complex as intricate wall murals.

The word “graffiti" comes from the Italian word graffiato, which means “scratched." Art historians believe the term arose from the fact that the earliest forms of graffiti were carved on walls with sharp objects.

Graffiti has been around a long, long time. In fact, it can probably be traced back to the first time someone used an animal bone to carve the first drawings on cave walls. However, since these drawings were probably created on the walls of what were homes at the time, some people don't consider them to be public and, therefore, not graffiti.

Examples of public graffiti date back to the time of the ancient Greeks and Romans. These ancient forms of graffiti often displayed declarations of love, political slogans and quotes popular at the time.

Today, graffiti is mainly applied with spray paint or marker pens. In most parts of the world, painting property without the owner's consent is considered vandalism. This is why many people consider graffiti to be a crime that should be punished under the law.

Others, however, believe graffiti is a legitimate form of street art. Today, graffiti is intertwined with hip hop culture and music. Street artists often use graffiti to express social and political messages.

On the other hand, graffiti is also often used by gangs to mark territory or commemorate gang-related activities. Public officials must balance the value of legitimate street art with pure vandalism related to criminal behavior.

Many public officials understand and recognize the value of public works of art. Some towns encourage public works of art — even graffiti — if it is approved in advance and serves a public purpose.

Some towns, however, have grown tired of battling unauthorized graffiti. Thanks to scientists who have developed special paints, these towns can now paint public areas with specialized paints that counteract graffiti. Instead of sticking to walls permanently, graffiti sprayed onto this special paint can be easily washed away.

The most common style of graffiti is the “tag." Tagging simply means painting one's name in one's own unique style. A graffiti writer's tag is like his or her personalized signature.

One well-known graffiti artist who helped bring graffiti into the mainstream in the 1980s was Keith Haring. Haring opened a store called the Pop Shop that sold products, like bags and t-shirts, which featured his graffiti art. Before he opened his store, his art could only be found on city walls.

Unlike Haring, however, many graffiti artists choose to remain anonymous. Because of the constant threat of legal action from those who oppose graffiti, many artists prefer to remain unknown rather than face problems with the law.

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