Why in html colour writed "COLOR"?

Question

Please answer

Answer 1

colour is written as color in American english

Answer 2

American made HTML

Answer 3

Fair question, but not sure how it's material to becoming a better coder.
An Englishman was primarily responsible for HTML at CERN (Geneva, Switzerland) but because the head of the computing department didn't see his project as a priority (even though his direct supervisor fully supported the project), he brought the project to the US (MIT) and worked on standardizing it there.