What Is Morse Code?

Who invented Morse code?

Morse code was developed in the 1830s and 1840s by Samuel Morse, an American artist and inventor, together with Alfred Vail. They built it for the electric telegraph, a machine that could send electrical pulses down a wire over long distances.

The first public telegraph message, sent by Morse in 1844, read "What hath God wrought". The original American Morse was later refined into International Morse Code, standardised in 1865, which is the version used around the world today.

How Morse code works

Every letter is a pattern of dots (short signals) and dashes (long signals). A dash lasts about three times as long as a dot. Short gaps separate the parts of a letter, longer gaps separate letters, and the longest gaps separate words.

The code is cleverly designed around how often letters appear in English. The letter E, the most common, is a single dot. The letter T is a single dash. Rare letters like Q and Y have longer patterns. That design let skilled operators send everyday text quickly.

How long is a dot compared to a dash?

Morse timing is defined in units, where one unit is the length of a dot. A dash is three units. The gap between the dots and dashes inside one letter is one unit, the gap between letters is three units, and the gap between words is seven units. Those five numbers are the whole timing standard.

Because everything is a multiple of the dot, speed is set by choosing how long a dot lasts. Send faster and every element and gap shrinks together, which is why Morse stays readable across a huge range of speeds. Speed is quoted in words per minute, measured with the reference word PARIS, chosen because its timing matches the average of ordinary English text.

Operators also use prosigns: letters run together without the usual gap to act as a single symbol. SOS is the best known, sent as one unbroken ...---... rather than three separate letters, which is why it cuts through interference so well.

Why Morse code is still used

Morse survives because it is simple and tough. A weak signal that would be lost as speech can still be copied as clean dots and dashes. Amateur radio operators use it every day, aviation navigation beacons identify themselves in Morse, and it remains a dependable fallback when conditions are poor.

It is also accessible: people who cannot speak or move easily have used Morse, tapped or blinked, to communicate. Its flexibility across sound, light and touch is part of why it has lasted nearly two centuries.