The codes are chosen to have suitable properties, e.g. Binary Golay code.
Morse code | Internal Revenue Code | The Chicago Code | The Da Vinci Code | Chapter 11, Title 11, United States Code | ZIP code | source code | International Code of Zoological Nomenclature | DVD region code | Criminal Code of Canada | Uniform Code of Military Justice | code | Baudot code | Universal Product Code | United States Code | QR code | International Civil Aviation Organization airport code | Code | binary | Zip Code Rapists | Napoleonic Code | Code of Federal Regulations | Code B | Title 10 of the United States Code | Source Code | International Air Transport Association airport code | Code of the Krillitanes | Code 42 Software | Chapter 7, Title 11, United States Code | Bible code |