What type of protocol is UDP considered to be?

UDP, or User Datagram Protocol, is classified as an unreliable and connectionless protocol. The term "unreliable" indicates that UDP does not guarantee the delivery of packets. There is no mechanism for error checking or recovery; if a packet is lost during transmission, UDP does not attempt to resend it. This lack of reliability makes UDP suitable for applications where speed is more critical than accuracy, such as video streaming or online gaming.

Being "connectionless" means that UDP does not establish a dedicated end-to-end connection before data transmission. Each packet, or "datagram," is sent independently, and there is no need for a handshake process to open a communication channel. This enhances its speed and efficiency, but it also means that packets can arrive out of order or not at all.

Understanding these characteristics helps clarify why UDP is favored for specific applications that prioritize speed over reliability.