The header area of my Web site features an image based on the photograph below which was taken in Grappa in Northern Italy.
You can see some graffiti in the background.

The word:
graffiti
comes from the Italian language. “Graffiti” is actually the plural of the word:
graffito
which is the Italian word for “a scratch”.
The term graffiti dates from 1851 and the disovery of ancient inscriptions scratched into the walls of the city of Pompeii. Unlike contemporary graffiti created using spray paint, the earliest graffiti were scratches.
Etymologically the word graffiti comes from the verb:
graffiare
which means “to scribble”.
Graffiti and Grammar
The Italian the word graffiti is a plural noun and its singular form is graffito. In English we use the term graffiti as a mass noun and rarely use the singular term graffito. Hence we say the graffiti was all over the wall rather than the graffiti were all over the wall.
Let’s look at these phrases in Italian, starting with the graffiti was all over the wall:
i graffiti era tutto la parete
And the graffiti were all over the wall:
i graffiti erano su tutta la parete
In English we rarely say the graffito was on the wall and instead we use the word graffiti – and this is also the case in spoken Italian.