Symbol encoding · Variable-length codes

Morse Code

Tap out letters in dots and dashes. The original digital protocol.

Morse is binary in disguise: every letter is a sequence of two symbols (dot, dash) plus timed gaps. The frequent letters get the shortest codes — E is a single dot — which is the same idea Huffman coding uses, 130 years later, to compress every JPEG and ZIP file you've opened.

Morse Code Machine

Type a message and hear it in Morse code

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Morse Code Reference

0-----1.----2..---3...--4....-5.....6-....7--...8---..9----.A.-B-...C-.-.

D-..E.F..-.G--.H....I..J.---K-.-L.-..M--N-.O---P.--.

Q--.-R.-.S...T-U..-V...-W.--X-..-Y-.--Z--..

What you just learned

Morse code was one of the first ways humans encoded information. A computer's binary (0s and 1s) works the same way — simple signals combined to represent anything.

What’s happening under the hood

›Two symbols per letter, variable length per letter — a prefix code (no letter's encoding is the prefix of another's).
›Letter frequency drove the length assignments. Samuel Morse counted type cases in a printer to find common English letters.
›Huffman (1952) generalized this idea into the optimal-prefix-code algorithm at the heart of every modern compression format.

Dig deeper

Phase 0 · How Computers Think

The concept you just explored is taught with full depth in the formal DURA curriculum.