Graffiti has existed for centuries, starting as simple written words and evolving to include elaborate wall paintings. It is now commonly created using spray paint and markers. While some see graffiti as art, most consider it vandalism as it is made without permission. Billboards are large outdoor advertising structures used to display advertisements to people in public areas like roads. They come in different sizes, with bulletins being the largest to allow visibility from vehicles. Opinions on graffiti and billboards are mixed, with most seeing drawbacks to graffiti due to it being dirty and sometimes used for gang messages, while billboards are seen as generally clean and informative.