Graffiti
genre of writing or drawing etched, scratched, scribbled, or sprayed (often, but not always illicitly) on a wall or other surface in a public place / From Wikipedia, the free encyclopedia
Graffiti (plural; singular: graffiti or graffito, however graffito is rarely used except in archeology) is marks, scratching or drawings made on a surface on a public place. It is often created with paint or spray paint (paint that is sprayed from a can). A single mark could be called a graffito but the word graffiti is usually used, meaning that there is more than one mark. The word comes from Greek γράφειν (graphein) meaning "to write".[1]
Graffiti can take the form of art, drawings or words. When done without a property owner's permission it can be considered vandalism. Sometimes it is just a person's name or a rude word. Sometimes it is a public political protest because graffiti is illegal without permission.