The words bawd, baud sound the same but have different meanings and spellings. Why do bawd, baud sound the same even though they are completely different words?
The answer is simple: bawd, baud are homophones of the English language.
Computer Science A unit of speed in data transmission equal to one bit per second.
A woman who keeps a brothel; a madam.
A woman prostitute.
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").