Classic Encoding Systems: Roman Numerals, Morse Code, and ASCII
How Roman numerals, Morse code, ASCII values, and simple ASCII checksums each encode information using a fixed lookup system.
Long before modern character encoding, these systems solved the same basic problem — representing information with a fixed, unambiguous symbol set.
Roman numerals: an additive/subtractive number system
Roman numerals build numbers from letter values (I=1, V=5, X=10, L=50, C=100, D=500, M=1000), generally adding values left to right but subtracting when a smaller value precedes a larger one (IV = 4, not 6). This subtractive rule is what makes converting to and from Roman numerals trickier than it first appears.
Morse code: dots, dashes, and timing
Each letter and digit maps to a fixed sequence of dots and dashes, originally designed for telegraph transmission. The system also encodes timing rules (gaps between letters and words), which is why manually decoding Morse code from raw dots and dashes without a reference is much harder than encoding it.
ASCII values: the numeric backbone of text
Every character has a corresponding ASCII numeric code — 'A' is 65, 'a' is 97, '0' is 48. This mapping underlies nearly all basic text processing, from sorting strings to detecting character types, since a computer ultimately compares and stores numbers, not letters.
ASCII checksums: a simple integrity check
Summing the ASCII codes of every character in a string ("A" + "B" = 65 + 66 = 131) produces a basic checksum. It's not cryptographically secure — many different strings can share the same sum — but it's a simple, fast way to spot accidental data corruption.
Encoding systems, old and new
Roman numerals, Morse code, and ASCII all solve "represent this information with a fixed symbol set" — just for very different eras and purposes. Try the Roman numeral converter, Morse code translator, ASCII value calculator, and ASCII checksum calculator.