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      console.log('Connected !');
      socket.emit('msg', confirm('What is your message?'));
    });
  });
</script>
```

### Restricting yourself to a namespace

If you have control over all the messages and events emitted for a particular
application, using the default `/` namespace works.

If you want to leverage 3rd-party code, or produce code to share with others,
socket.io provides a way of namespacing a `socket`.

This has the benefit of `multiplexing` a single connection. Instead of
socket.io using two `WebSocket` connections, it'll use one.

The following example defines a socket that listens on '/chat' and one for
'/news':

#### Server side

```js
var io = require('socket.io').listen(80);

var chat = io
  .of('/chat');
  .on('connection', function (socket) {
    socket.emit('a message', { that: 'only', '/chat': 'will get' });
    chat.emit('a message', { everyone: 'in', '/chat': 'will get' });
  });

var news = io
  .of('/news');
  .on('connection', function (socket) {
    socket.emit('item', { news: 'item' });
  });
```

#### Client side:

```html
<script>
  var socket = io.connect('http://localhost/')
    , chat = socket.of('/chat')
    , news = socket.of('/news');

  chat.on('connect', function () {
    chat.emit('hi!');
  });

  news.on('news', function () {
    news.emit('woot');
  });
</script>
```

### Sending volatile messages.

Sometimes certain messages can be dropped. Let's say you have an app that
shows realtime tweets for the keyword `bieber`. 

If a certain client is not ready to receive messages (because of network slowness
or other issues, or because he's connected through long polling and is in the
middle of a request-response cycle), if he doesn't receive ALL the tweets related
to bieber your application won't suffer.

In that case, you might want to send those messages as volatile messages.

#### Server side

```js
var io = require('socket.io').listen(80);

io.sockets.on('connection', function (socket) {
  var tweets = setInterval(function () {
    getBieberTweet(function (tweet) {
      socket.volatile.emit('bieber tweet', tweet);
    });
  }, 100);

  socket.on('disconnect', function () {
    clearInterval(tweets);
  });
});
```

#### Client side

In the client side, messages are received the same way whether they're volatile
or not.

### Getting acknowledgements

Sometimes, you might want to get a callback when the client confirmed the message
reception.

To do this, simply pass a function as the last parameter of `.send` or `.emit`.
What's more, when you use `.emit`, the acknowledgement is done by you, which
means you can also pass data along:

#### Server side

```js
var io = require('socket.io').listen(80);

io.sockets.on('connection', function (socket) {
  socket.on('ferret', function (name, fn) {
    fn('woot');
  });
});
```

#### Client side

```html
<script>
  var socket = io.connect(); // TIP: .connect with no args does auto-discovery
  socket.on('connection', function () {
    socket.emit('ferret', 'tobi', function (data) {