title: "[, ...args]" in Socket.io docs
body: <p><a href="https://socket.io/docs/server-api/#socket-emit-eventname-args-ack" rel="nofollow noreferrer"><code>socket.emit(eventName[, ...args][, ack])</code></a></p>
  
  <p>Hello everyone. I just had a simple question. When I'm reading through documentation. The thing I find a little confusing is what certain things mean. So I know if you have something like <code>[, ack]</code>. That means it's optional but what about <code>[, ...args]</code>. I'm guessing it means it's optional too and you can specify more than one argument but I'm not sure? If anyone could help me out and link me a good wiki/resource about understanding documentation or explain it. I'll gladly appreciate it.</p>