Graffiti (both singular and plural; the singular graffito is very rare in English except in archeology) is writing or drawings made on a wall or other surface, usually without permission and within public view. Graffiti ranges from simple written words to elaborate wall paintings, and has existed since ancient times, with examples dating back to ancient Egypt, ancient Greece, and the Roman Empire.
In modern times, spray paint and marker pens have become commonly used graffiti materials, and there are many different types and styles of graffiti; it is a rapidly developing art form.
Graffiti is a controversial subject. In most countries, marking or painting property without permission is considered by property owners and civic authorities as defacement and vandalism, which is a punishable crime, citing the use of graffiti by street gangs to mark territory or to serve as an indicator of gang-related activities. Graffiti has become visualized as a growing urban “problem” for many cities in industrialized nations, spreading from the New York City subway system in the early 1970s to the rest of the United States and Europe and other world regions. On the other hand, graffiti artists, particularly marginalized artists with no access to mainstream media, resist this viewpoint to display their art or political views in public locations.