Assuming One Morse Forever
American landline Morse ≠ modern International radio Morse.
Short accurate history from American landline telegraph to International Morse — the standard used today.
Direct answer: Morse code began as 1830s American landline telegraph code and evolved into International (Continental) Morse — the ITU radio standard used worldwide today (and on this site).
Samuel Morse and Alfred Vail developed early American telegraph encoding in the 1830s–1840s for wire circuits. Europe’s Continental Morse adapted patterns for different line conditions. Wireless telegraphy needed one shared radio alphabet — International Morse became that standard.
Compare systems: American vs International. Live charts: International Morse.
Keep history tied to the code you actually send today.
American landline Morse ≠ modern International radio Morse.
Authority comes from linking history to the live ITU chart.
SOS was chosen for clarity of pattern — see the SOS page for facts.