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Communication at light speed

In the 1950s, people only had a few options for communicating with each other over long distances: a telephone call, a telegram, or a mailed letter.
But then computers, the Internet, and mobile phones happened. Nowadays, we can send an email, write a short text message, post on social media, or use any one of many popular messaging apps. Thanks to all those options, we can choose the communication medium that's best for our message's audience and purpose.
Whatever we choose, our messages arrive nearly instantaneously at their destination: popping up in email inboxes, triggering push notifications on phones, or appearing in social media feeds.
The best part? Everything's asynchronous, so we don't actually need to drop everything and reply immediately. We can, if we want, but we can also take our time.
Let's explore email, SMS, and social media in more depth, and consider the differences in how they enable communication and information dissemination.

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