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/*
Long polling is a simple technique that can be implemented using only HTTP,
but it is not as efficient as WebSockets because it requires a new HTTP
request/response cycle for each message.
WebSockets is a more efficient technology than long polling because it uses a
single TCP connection for bi-directional communication. However, it is not
supported by all browsers, so you may need to use a fallback technology (such
as long polling) for older browsers.
SignalR is built on top of WebSockets and provides a higher-level API that
makes it easier to add real-time functionality to your application. It
automatically falls back to other technologies (such as long polling) if
WebSockets are not available, so you don't have to worry about browser
compatibility or network limitations.
*/