RTMP (Real-Time Messaging Protocol) is a protocol designed by Adobe for streaming media (audio, video, data) over TCP. It's optimized for low-latency ingest from encoders (cameras, broadcast equipment) to streaming servers. RTMP is not consumed directly by browsers (no native support), but servers use it to ingest streams and then transcode them to HLS/DASH for web playback. RTMP remains the industry standard for encoder-to-server communication, even though WebRTC and HLS dominate playback. If you're building a live streaming platform, RTMP ingest is essential.