The words read, red, redd sound the same but have different meanings and spellings. Why do read, red, redd sound the same even though they are completely different words?
The answer is simple: read, red, redd are homophones of the English language.
To examine and grasp the meaning of (written or printed characters, words, or sentences).
To utter or render aloud (written or printed material): read poems to the students.
To have the ability to examine and grasp the meaning of (written or printed material in a given language or notation): reads Chinese; reads music.
To examine and grasp the meaning of (language in a form other than written or printed characters, words, or sentences): reading Braille; reading sign language.
The hue of the long-wave end of the visible spectrum, evoked in the human observer by radiant energy with wavelengths of approximately 630 to 750 nanometers; any of a group of colors that may vary in lightness and saturation and whose hue resembles that of blood; one of the additive or light primaries; one of the psychological primary hues.
A pigment or dye having a red hue.
Something that has a red hue.
Chiefly Pennsylvania To clear: redd the dinner table.
redd up To tidy: redded up the front room.
A spawning nest made by a fish, especially a salmon or trout.
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.