UDP stands for User Datagram Protocol. It is an Open Systems Interconnection (OSI) transport layer protocol. UDP sends data consistently without an error check, and is very useful for systems to simply generate data in real time.
Why is this important? Many devices such as sensors send out continuous data and that is all. It is important to have a protocol that is not going to jitter and hang while worrying about errors. UDP allows this data to flow freely while relying on the receiving application to handle it.