(CNN) - Monday is a special anniversary for the communications industry. It was 20 years ago that Neil Papworth sent the first-ever text message.
He had to use a computer terminal to send the message to a colleague's cellphone: "Merry Christmas."
"Texting" had a slow start, but eventually it surged in popularity, especially when it became cheaper than calling.
It is the single most-widely used application in the world; 81 percent of mobile phone subscribers use it.
Now, free alternatives like instant messaging apps are becoming more and more popular, and text messaging is in decline.