The words color, culler sound the same but have different meanings and spellings. Why do color, culler sound the same even though they are completely different words?
The answer is simple: color, culler are homophones of the English language.
That aspect of things that is caused by differing qualities of the light reflected or emitted by them, definable in terms of the observer or of the light, as:
The appearance of objects or light sources described in terms of the individual's perception of them, involving hue, lightness, and saturation for objects and hue, brightness, and saturation for light sources.
The characteristics of light by which the individual is made aware of objects or light sources through the receptors of the eye, described in terms of dominant wavelength, luminance, and purity.
A substance, such as a dye, pigment, or paint, that imparts a hue.
One who picks or chooses; esp., an inspector who selects wares suitable for market.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition, from Wiktionary, Creative Commons Attribution/Share-Alike License and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.
If they are spelled the same then they are also homographs (and homonyms); if they are spelled differently then they are also heterographs (literally "different writing").