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Frontend Glossary

Frontend engineering · Networking

Server-Sent Events

Also called: SSE, EventSource, Server push over HTTP

The server pushes text events over one long-lived HTTP response; the browser listens with EventSource—great for one-way streams.

In detail

SSE focuses on server to browser updates: AI token streams, progress bars, simple notifications. It rides HTTP and has built-in retry semantics, often easier through proxies than WebSockets (environment-dependent).

Limits: mostly one-way; browsers cap concurrent connections per origin; binary is awkward versus WebSockets. If the client must send high-frequency ups, use WebSocket.

It pairs naturally with AI Streaming: one event per token or chunk.

Developer info
Term ID
eng-sse
DOM selectors
No DOM cues. This concept isn't detected directly on a page.
Priority
1 · when several match at the same level, the higher priority wins
Version
v1 · updated Oct 5, 2026