History & CultureHow it works

How Morse code works and why E is a single dot.

Morse code uses short and long signals: a dash lasts three dots, letters are separated by a gap of three dots, words by seven. Frequent letters got short codes: E is one dot, T one dash. Rare ones like Q need four symbols. That made telegraph transmission faster. SOS is three short, three long, three short.

Useful: Frequent things short, rare things long: the same principle lives in every data compression today.

Source: en.wikipedia.org

Kommunikation TechnikTelegraf

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