Morse code decoding converts sequences of dots (.) and dashes (-) back into letters, numbers, and punctuation by matching each pattern to the international Morse code standard. For example, '.... . .-.. .-.. ---' decodes to 'HELLO' because each space-separated group represents one character: '....' is H, '.' is E, '.-..' is L, '.-..' is L, '---' is O. The decoder expects spaces between letters and forward slashes (/) or longer pauses to indicate word boundaries, transforming '.... . .-.. .-.. --- / .-- --- .-. .-.. -..' into 'HELLO WORLD'.
Morse code is a variable-length encoding system where common letters (E = '.', T = '-') use short patterns, while rare letters (Q = '--.-', J = '.---') use longer sequences. This efficiency made Morse code ideal for telegraphy, where transmission time was costly. Decoding requires recognizing these patterns and handling timing conventions: one unit for dots, three units for dashes, one unit of silence between dots and dashes within a character, three units between characters, and seven units between words. Digital decoders use spaces and slashes to represent these timing boundaries.
The international Morse code standard (adopted in 1848 and revised in 1938) supports A-Z letters, 0-9 digits, and common punctuation (period, comma, question mark, apostrophe, exclamation, slash, parentheses, ampersand, colon, semicolon, equals, plus, minus, underscore, quotation marks, dollar sign, at symbol). Some variants exist—American Morse code differs slightly from international Morse—but this decoder follows the international standard used by amateur radio operators worldwide. Decoding accuracy depends on proper spacing and adherence to standard character mappings.
