What Is UDP?
UDP — the User Datagram Protocol — the fast, connectionless transport protocol that sends data without guarantees, ideal for real-time traffic like voice, video and gaming.
How it works
UDP skips TCP's handshake, acknowledgments and retransmission — it just sends datagrams and moves on. This means no delivery guarantee and no ordering, but also minimal overhead and latency. For live voice or video, a dropped packet is better than the delay of retransmitting it, which is exactly why they use UDP.
Why it matters
UDP is the counterpart to TCP, and knowing when each applies is fundamental networking knowledge. Its speed-over-reliability trade-off explains why DNS, VoIP, streaming and gaming choose it. See TCP vs UDP for the direct comparison.
Frequently asked questions
What is UDP?
The User Datagram Protocol — a fast, connectionless transport protocol that sends data without delivery guarantees, minimising overhead and latency.
Why does UDP have no error recovery?
By design — skipping acknowledgments and retransmission makes it fast and low-latency, which suits real-time applications where timeliness beats perfect delivery.
What applications use UDP?
DNS lookups, VoIP, live video streaming and online gaming — where low latency matters more than guaranteed, ordered delivery.
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