A myth is a story which is not true. It means it is still subject to debate. Myths may be very old, or new (for example: urban myths). There may not be records or other proof that they happened, but at least some parts of myths may be true. We know about them from older people telling them to younger people. Some myths may have started as 'true' stories but as people told and re-told them, they may have changed some parts, so they are less 'true'. They may have changed them by mistake, or to make them more interesting. All cultures have myths. Stories about the Greek and Roman gods and goddesses are myths.