Color Vs Colour : What is the difference?

Color and colour are alternative spellings of the same word. However, many people have not been able to understand the difference between these two terms thereby using them interchangeably, which confuses their audience.

American English Vs British English

When choosing between color and colour, keep in mind that both spellings are correct. The former is the preferred spelling for American English, while the latter is the preferred spelling for British English. This means that the spelling "color" (with no "u") is used in the United States of America. The spelling "colour" (WITH a "u") is used in the United Kingdom, and in all parts of the British Commonwealth: Australia, India, Ghana, Canada, etc.

Color as computer input

The other difference is that color is a computer input means computer understands color instead of colour and most APIs use American grammar. So, you should use the American spelling of color. 99% of code out there uses this, even including much of the code written by British or Australian English speakers. If you use something different, you (or someone else that uses your code) are just going to end up forgetting which to use at some point and making a needless mistake.

Centuries old..

Both spellings are many centuries old. It was Noah Webster, insisting on only including the -or ending in his 1828 American dictionary, who most deeply influenced American usage. Similarly, Dr Johnson, in his earlier English dictionary, insisted on -our endings. Color and colour are a good example of spelling differences between American and British English. Americans have standardized around different spelling conventions from other parts of the world.

Spelling Differences

There is a multiplicity of spelling differences between British and American English. The same applies to other words such as humour/humor, honour/honor, behaviour/behavior, harbour/harbor, vapour/vapor, vigour/vigor, favourite/favorite, rigour/rigor, valour/valor, endeavour/endeavor. The distinction extends to all derivatives of the word. Colored, coloring, colorer, colorful, and discolor are the U.S. spellings, and coloured, colouring, colourer, colourful, and discolour are preferred outside the U.S.