The words light, lite sound the same but have different meanings and spellings. Why do light, lite sound the same even though they are completely different words?
The answer is simple: light, lite are homophones of the English language.
Spiritual awareness; illumination.
Liable to change; fickle.
Physics Electromagnetic radiation that has a wavelength in the range from about 4,000 (violet) to about 7,700 (red) angstroms and may be perceived by the normal unaided human eye.
Slang Having less substance or weight or fewer calories than something else: "lite music, shimmering on the surface and squishy soft at the core” ( Mother Jones).
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition 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").