It is exactly 25 years since the first text message was received on a mobile phone.
The SMS - which simply read 'Merry Christmas' had to be typed on a computer before being sent between two Vodafone colleagues.
It contained no abbreviations and certainly no emojis.
Elizabeth Bruton from London's Science Museum says it was a hugely significant development.
She said: "For the very first time we have mobile telephones which are more than just literal mobile telephones.
"We are moving beyond voice communications, so the SMS can be considered the first step towards the modern smartphone.
Neil Papworth, the man who sent the text, says he had no idea at the time how significant the development was.
He said: "I know that the first systems we put in, would do something like two messages per second whereas nowadays operators are probably doing tens of thousands of messages a second."