A lightweight, connectionless protocol used for fast, low-latency data transmission where reliability isn't critical.
UDP is often chosen when speed is more important than accuracy, such as in real-time communication. It avoids the overhead of connection management and retransmission logic found in TCP.
Use UDP when you need speed and can tolerate some data loss, like in live video streaming, online gaming, or VoIP.
You need to know
Connectionless - No handshake or session; data is just sent, reducing latency.
No guarantees - UDP doesn’t ensure delivery, order, or data integrity (your app has to handle that if needed).
Low overhead - Fewer protocol features mean smaller, faster packets, ideal for high-throughput or real-time systems.
Popular technologies
QUIC - A modern protocol built on UDP, used by HTTP/3 for faster, secure web transport.
WebRTC - Uses UDP under the hood for peer-to-peer real-time communication (e.g., video calls).
DNS - Domain Name System often uses UDP for quick query responses.
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