Twenty years ago this month, the SMS text message was born in London. "Merry Christmas," typed software engineer Neil Papworth, using a personal computer, to his friend Richard Jarvis, an employee at Vodafone, using a mobile phone.
One year later, Nokia introduced the first mobile phone that allowed text messages to be sent within the same network. The technology grew slowly until 1999, when text messages were finally deliverable across different networks. That, along with the growth of mobile phone usage, turned text messaging into a phenomenon.
The text message has had a good life - two decades is a long time in the tech world - but it's slowly being replaced by another phenomenon: WhatsApp, the mobile messaging app created by a start-up business from California in 2009.
It works the same way, mostly. You still type messages with shorthanded spelling and weird acronyms, and you're still annoying the person sitting across from you during dinner with it, but it's free (after a one time 99 US cents download fee), assuming you have access to the internet.
And people like free. WhatsApp is the top overall paid app in the Apple App Store in 119 countries; it delivers more than 10 billion messages a day; and the big tech blogs estimate WhatsApp's user base at more than 200 million (some say 300 million).
SMS text messaging numbers, predictably, have dropped as a result. The New York Times reported early this year that text messaging is declining in most parts of the world. In Hong Kong, there was a "steep decline in text messaging on Christmas Day [2011]", according to figures released by local mobile companies. It's safe to assume the figure will drop again this Christmas.