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Good day to all, please help us solve this problem. There is a chat, and I want to do such a thing, when a person is sitting ... can update it constantly, without necessarily finding a person on this tab? The analog can be seen in the Vkontakte dialogs.

I want to make a chat. The project is small, there will be no special loads. Which is better to use, websockets or ajax? I'm leaning towards ajax because of the ease of implementation, let me?

The question is, how do I send messages to all users in the chat, and not just to the one who sent it? Tell me, preferably wi ... nd(msg); } }); } } Tell me how to correctly add clients to the collection to send them all messages