Note: Do not rely on this information. It is very old.
Graffiti
Graffiti, rude scribblings scratched with a sharp instrument, or inscribed in red chalk or charcoal on the walls and pillars of ancient buildings in southern Italian towns. They are especially abundant at Pompeii, and there are several on the Palace of the Ceesars and Nero's Golden House at Rome. They include both drawings and remarks or quotations, and have much the same general character as similar effusions of the present day, but some of them are memoranda relating to the events of daily life. Their importance consists in the light they throw on the life and speech of the people at the time. The graffiti found in the catacombs, which are of a different character, were placed there by the early Christians.