What is "pizzino"

Pizzino (pl. pizzini) is an Italian language word derived from Sicilian language equivalent pizzinu. Despite it generically meaning "small piece of paper", the word is now widely used to refer to small slips of paper that the Sicilian Mafia uses for high-level communications. Sicilian Mafia boss Bernardo Provenzano is among those best known for using pizzini, most notably in his instruction that Matteo Messina Denaro become his successor. The pizzini of other mafiosi have significantly aided police investigations.