Just as it says in the name, real-time communication is the handling of requests concurrently and efficiently. Whether it is a chat/messaging app, an email service, a game server or any collaborative online project (for example, Excalidraw), there are a few different ways of handling real-time communication, but the most common is through the use of WebSockets. Other options for handling real-time communications include MQTT protocol and server-sent events, among others.
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