I make three crosses - even when signing a contract
News News blog
Already in the Middle Ages it was quite usual to individualize one's signature with a graphic symbol (e.g. a cross).

When, in addition to the first name, surnames were officially recorded throughout the population and literacy had advanced, signatures based on symbols lost their meaning.
Illiterate people can still sign official documents with "three little crosses" as hand signs. However, this symbolic signature must be notarized. "A signature that is not made with the name signature, but with a mere hand sign - the best known are three crosses - requires certification by a notary public." (§ 126 dBGB).