Socket#to(room:String):Socket Socket#in(room:String):Socket

[smart--petea]

Sets a modifier for a subsequent event emission that the event will only be broadcasterd to sockets that have joined the given room.

To emit to multiple rooms, you can call to several times.

var io = require('socket.io')();
io.on('connection', function(socket) {
  socket.to('others').emit('an event', { some: 'data'});
});