The first SMS in history was sent on 3 December 1992 by Neil Papworth, an engineer at Sema Group, to the phone of Richard Jarvis, then at Vodafone. The message ran to two words: "Merry Christmas". A telling detail: it was typed on a computer — phones of the era could not yet compose an SMS.
A service designed as an afterthought
What stands out in hindsight is that nobody expected much of SMS. It had been specified in the GSM standard as a secondary function, meant mostly for service notifications — you have a voicemail, your credit has run out. The bulk of the network was built for voice.
That modesty is what explains its shape. SMS has no channel of its own: it travels in the signalling channels, the ones the network uses to coordinate itself. Those channels had spare room, and SMS moved in. Hence the founding constraint: 140 bytes, not one more.
Where the 160 characters come from
German engineer Friedhelm Hillebrand, who worked on GSM standardisation, is generally credited with the choice of limit. The story goes that he typed dozens of sentences on a typewriter and found that most everyday messages fitted in under 160 signs. Postcards and telexes, examined as points of comparison, pointed the same way.
The number is not arbitrary for all that: 140 bytes divided into 7-bit units gives exactly 160 characters. It is where a hunch about usage meets a binary constraint. We set out that calculation in our article on the 160-character limit.
The adoption nobody planned for
Take-off was slow. It took phones that could enter text, operators willing to allow messages between competing networks — far from obvious at the outset — and pricing that stopped deterring people. Then usage exploded, driven by an audience the industry had not targeted: teenagers.
SMS then imposed its own language, built from abbreviations born of constraint. Writing short was not a style, it was an economic and technical necessity.
What survived, and why
Thirty years on, messaging apps have taken over personal conversation. SMS holds a place no app really contests: it works everywhere, on any phone, with no installation, no account and no data connection. That is what makes it the channel for login codes, alerts and appointment reminders — everything that has to arrive unconditionally.
Its announced successor, RCS, brings the modern features it lacks. But it depends on the handset, the operator and the country, and falls back to SMS whenever it is unavailable. We compared the two formats in detail.
That may be the most enduring paradox of the story: SMS remains indispensable precisely because it stayed minimal.
