There is some confusion between the words homonyms, homophones and homographs. These words all derive from the Greek with the prefix 'homo-' meaning 'the same'.
Homographs (literally 'same writing') are words which are spelled the same way, but have different meanings.
For instance the word 'bow' (the verb meaning to bend at the waist), 'bow' (meaning part of a ship) and 'bow' (the weapon used with arrows) are homographs. Homographs may have different pronunciations, as with the first two meanings of bow, above and the last one. Homographs may also have the same pronunciation, as with the first two given meanings of 'bow'.
Moreoever, two homographs may be the same part of speech (for instance, the latter two meanings of 'bow' are both nouns) or different (the first meaning was a verb, although there is also a related noun, (eg 'he gave a polite bow'). Wikipedia has a lengthy list of English and American homographs.
Homophones (literally 'same speaking') are words which are pronounced in the same way, but spelled differently.
For example, 'bare' and 'bear' are homophones. So are 'see' and 'sea'. Homophones can also refer to different ways of spelling the same sound, for instance 'f' and 'ph' in English.
Homonyms (literally 'same name') are words which are pronounced OR spelled the same, but have different meanings. So homonyms include both homophones and homographs.
All homonyms, and particularly homophones, are fascinating because they reveal linguistic differences between the various English-speaking countries. Indeed, even within England there are differences of pronunciation across the country. In some parts, for instance, the word 'look' is pronounced the same as the name 'Luke'. However I aim on these pages to list homophones which would be accepted by the majority of British English speakers rather than regional variations within the country.
Readers from other English-speaking nations, particularly those in the USA, may be surprised at some of the words which we count as homonyms, and at some of the ones we don't. For instance, 'do' and 'due' are homophones in US English, but not in British English.
To see tables of homonyms through the alphabet, see the following pages: