quote:

When most people think of a typical text message, they're likely referring to Short Message Service, or SMS, a suite of protocols that has been a component of cellular networks for decades. With SMS, messages of up to 160 characters can be sent and received between devices residing on or across mobile communications networks.

In the last few years, however, a newer messaging format has emerged: Rich Communication Services (RCS). RCS is a revamped form of messaging that comes with a host of functionality and security features that SMS simply cannot provide.

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The key difference between RCS and SMS is that SMS sends messages over the cellular network, while RCS content requires data connectivity before it can be transmitted. In some situations where data connectivity is not available, it's still possible to send and receive SMS-supported messages. With the expansion of LTE and 5G, however, internet connectivity is plentiful in most areas, enabling a feature-rich service.