This contribution looks at materials from Dunhuang that are relevant to the study of graffiti. As can be observed from statements in poems preserved on the verso of one Dunhuang scroll, the practice of scratching names into cave walls was not always welcomed, regardless of the skills of the writer. An analysis of the textual structure of nine inscriptions from Mogao Cave 108 reveals telling differences between the inscriptions, which were likely done by persons of different social standings. Among them, one inscription is also found as one of several mnemonic lines on as many as ten Dunhuang manuscripts. This suggests similar functions for the blank spaces on walls and manuscripts. Since the mnemonic lines on the manuscripts indicate an educational context, it is very likely that students also scratched these lines onto the walls.