The Unique Device Identification (UDI) is a unique number, or combination of numbers and letters, given to a medical device. It is in two parts: one part identifies the device the other part identifies the producer. The aim of the UDI system is to improve patient safety: it means devices can be traced and recalled more easily, and it makes counterfeiting (production of fake copies) more difficult. The UDI is given to medical devices in addition to other labelling requirements.