WebSockets

Web sockets make it cheaper to talk to your servers.

Benefits

Connecting to a server takes some time, so with web sockets, you make that connection once and then keep using. The major benefits of this are:

1. It is faster to send messages. No need to do a bunch of work for every single message.

2. The server can push messages to you. With normal HTTP you would have to keep asking for changes, but a web socket, the server can talk to you whenever it wants. This means there is less unnecessary network traffic.

Learn

The best way to learn how to use this library is to read guide.elm-lang.org, particularly the section on The Elm Architecture.