UDP
also: User Datagram Protocol
UDP (User Datagram Protocol) is a lightweight, connectionless network protocol that sends data packets without establishing a connection or guaranteeing delivery. It prioritizes speed over reliability.
UDP is a transport-layer protocol in the TCP/IP suite that allows applications to send data across a network quickly with minimal overhead. Unlike TCP, UDP does not establish a connection before sending data, does not retransmit lost packets, and does not guarantee that data arrives in order.
UDP is ideal for applications where speed matters more than perfect accuracy, such as video streaming, online gaming, VoIP, and DNS queries. For example, a video call can tolerate losing a few video frames without noticeably degrading the conversation, but the real-time nature of the call requires minimal delay.
UDP packets are called datagrams and include a source port, destination port, message length, and optional checksum. The trade-off is simplicity and low latency at the cost of reliability—applications using UDP must handle their own error checking if needed.