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Computers and the Internet

Unit 5: Lesson 1

Communication innovations
Computing
Computers and the Internet
Computing innovations
Communication innovations
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SMS

Google Classroom
Merry Christmas
That was the first SMS message, sent in December 1992 from a software developer in the United Kingdom.
SMS was designed as a "short message service" between mobile phones. The messages needed to be short because mobile phone networks had constrained bandwidth at the time. A German engineer proposed the 160 character limit, justifying it based on the average length of postcard messages and telegrams. start superscript, 1, end superscript
An SMS on an early mobile phone. Message says "It is gr8 2 c u 2nite. TY 4 dinner."
An SMS from the early 2000s that uses "textspeak" to fit a longer message in less characters. Image source: Miss Puzzle
The 160 character limit still holds today, but now many mobile phones make it seem like there is no longer a limit by splitting long messages into multiple pieces and stitching them back together again.
SMS learned a few new tricks too: SMS messages can be sent to multiple recipients and include images. Still, compared to email, it's fairly limited in its functionality.
Despite its limitations, SMS is remarkably popular. In the early 2000s, SMS usage shot up in countries without reliable Internet service, since SMS travels over the cellular networks.
Now that many more countries do have high-speed wireless Internet, SMS is competing with messaging apps like WhatsApp and WeChat. Even so, it remains a common form of messaging since it works between any two phones on any network; no app download needed!
Just like email, SMS was originally intended for one-to-one communication, but it's now used as a way for governments and businesses to broadcast messages to many phones at once.
A government agency can send SMS messages to subscribed residents with alerts about missing persons, severe weather, and major road closures. start superscript, 2, comma, 3, end superscript
Screenshot of an iPhone with three SMS messages on it. The first says "AC ALERT: This is an advisory message from Alameda County. The National Weather Service has issued an excessive heat advisory for Alameda County." The second says "BERKELEY PD: AVOID the area of Cedar Street/9th Street due to a traffic collision. Some roads closed" with a link to "nixle.us/AYTG8". The third says "BERKELEY PD: Please help us locate at at-risk missing person" with a link to "nixle.us/AYP42".
Alerts from the Berkeley Police Department and Alameda County
Similarly (though not quite as life-saving!), businesses can send SMS messages to customers to entice them with promotions. Mobile phone users are a captive audience; the average US smartphone user touches their phones more than 2,000 times a day and the average open rate for SMS messages is as high as 98%. start superscript, 4, comma, 5, end superscript
Screenshot of 3 SMS marketing messages. First SMS says "We miss you here at Mommy's Trading Post! You get 10% off any 1 second-hand clothing item on your next visit. Reply YES to save. Exp 4/17." Second SMS says "Thanks for visiting Barefoot Movement. Based on this visit, how likely would you be to recommend us? Reply 0-10 (best). STOP to end msgs" Third SMS says "Hi Pamela, It's our Welcome Back Week. Call NOW to take advantage of our 60% OFF Welcome Back deal at MIssion Yoga. Reply STOP to OptOut"
SMS marketing messages from local businesses.
🤔 What messaging app do you use? Do you prefer to communicate with friends by texting, calling, or some other medium? How has text-based communication changed your social interactions?
🙋🏽🙋🏻‍♀️🙋🏿‍♂️Do you have any questions about this topic? We'd love to answer—just ask in the questions area below!

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