1.Generally, people who are nice, clean cut, sweet, polite, simple, naive; usually young and teenybopperish. They are usually more friendly and easier to get along with than Rolling Stones people. They were nicely dressed and coiffed, and respected their elders.
2.During the 60's, you were generally regarded as either a Beatles person, or a Rolling Stones person
3.People who liken themselves to, or possess the qualities that are of The Beatles
4.Contrary to the Rolling Stones people
The term was confirmed by the Beatles themselves in a 1965 Playboy interview, where they said it was originally used by fan magazines. They picked up the term and used it to (sometimes humorously) make sure fangirls knew how perfect they were.
Paul: That's not true, Beatle People!
George: Yeah, I'M the one who has been cheating on John's wife.
*Disclaimer: Not real quotes. As far as we know.