A "Knut" is a unit of currency in the wizarding world of Harry Potter, created by author J.K. Rowling. It is a bronze coin worth one-twentieth of a Sickle, which is the main currency used by witches and wizards. The currency system in the wizarding world consists of three main coins: Knuts, Sickles, and Galleons. In the Harry Potter series, Knuts are often used for small purchases, such as sweets or minor magical items. The exchange rate is 29 Knuts to a Sickle and 17 Sickles to a Galleon, making Knuts the smallest denomination in the wizarding currency system.