The words we, wee, whee sound the same but have different meanings and spellings. Why do we, wee, whee sound the same even though they are completely different words?
The answer is simple: we, wee, whee are homophones of the English language.
Used by the speaker or writer to indicate the speaker or writer along with another or others as the subject: We made it to the lecture hall on time. We are planning a trip to Arizona this winter.
Used to refer to people in general, including the speaker or writer: "How can we enter the professions and yet remain civilized human beings?” ( Virginia Woolf).
Used instead of I, especially by a writer wishing to reduce or avoid a subjective tone.
Used instead of I, especially by an editorialist, in expressing the opinion or point of view of a publication's management.
Very small; tiny. See Synonyms at small.
Very early: the wee hours of the morning.
Scots A short time; a little bit.
Used to express extreme pleasure or enthusiasm.
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").