british and american english spelling difference. Same meaning

They have the same meaning and pronunciation. The US spelling (color) follows the pronunciation more closely. The UK spelling (colour) follows the European spelling rules more closely (compare with French 'la couleur'). General rule: use only one or the other (only UK or only US spellings) - never mix them.

In USA, they don't use U when it comes with OU. In british spelling it is colOUr and in USA spelling, it is colOr. Other examples are: honour=honor, humour=humor, endevour=endevor

Colour = UK spelling Color = US spelling check more difference http://www2.gsu.edu/~wwwesl/egw/jones/differences.htm

agree with upstairs