A myth is a traditional prose narrative that a culture treats as a truthful account of what happened in the remote past. Myths are often sacred, set in a different or earlier world, and feature gods or other non-human beings as principal characters. A legend is also told as true, but it is set in a more recent past when the world was much as it is today, and its main characters are usually human heroes—stories about figures such as King Arthur or Robin Hood are classic examples. Folklorist William Bascom’s widely cited distinction turns on belief, time, place, sacred or secular attitude, and whether the leads are divine or human.
Source: Grand Valley State University — Myth FAQs (William Bascom’s definitions)