WebSockets
ExplainedProtocol / format
Also known as: WS
Protocol for real-time, two-way communication between client and server over one persistent connection.
WebSockets, explained
Written by EduVerseWhat it is
WebSockets is a protocol for a long-lived, two-way connection between a browser and a server. It starts as an ordinary HTTP request that asks to upgrade the connection, and from then on both sides can send messages at any moment. Addresses start with ws://, or wss:// for the encrypted version.
Why teams use it
With plain HTTP the client always has to ask first, so live updates mean polling the server every few seconds, which is wasteful and slow. Over a WebSocket the server pushes new data the moment it exists. The trade-off is that open connections cost server resources, and spreading them over several servers takes extra work.
An example from work
You build a chat feature and open DevTools. In the Network tab, filtered on WS, you find one request with status 101 Switching Protocols, and its Messages tab lists every message sent and received as it happens. After a deploy the connection drops, so your client code needs to reconnect on its own.
Our own explanation, not a quote from the book.
Where it fits
Chat, live feeds, multiplayer games, real-time dashboards
Coverage in the book
Explained and compared with alternatives, so you know where and why it’s used.
