They’re an “always open” connection between your client and the setver. HTTP works by the client sending a request with a return address and the server sending a reply to that address. Wbsockets then create a “socket” connection to the client that can send data at any time without having to open a new connection, negotiate the protocol, and send all the return address/header information/ etc.

Since the socket is already open, no new context is needed and small bits of data can be sent back and forth quickly.