Alone in a room in his home in Bonn, Germany, Friedhelm Hillebrand sat at his typewriter, tapping out random sentences and questions on a sheet of paper.

As he went along, Hillebrand counted the number of letters, numbers, punctuation marks and spaces on the page. Each blurb ran on for a line or two and nearly always clocked in under 160 characters.

That became Hillebrand’s magic number — and set the standard for one of today’s most popular forms of digital communication: text messaging.

“This is perfectly sufficient,” he recalled thinking during that epiphany of 1985, when he was 45 years old. “Perfectly sufficient.”