Much of the folklore about fairies revolves around protection from their malice. Although in modern culture they are often depicted as young, sometimes winged, humanoids of small stature, they originally were depicted quite differently: tall, radiant, angelic beings or short, wizened trolls being two of the commonly mentioned forms. One common theme found among the Celtic nations describes a race of diminutive people who had been driven into hiding by invading humans. When considered as beings that a person might actually encounter, fairies were noted for their mischief and malice. Fairies are generally described as human in appearance and having magical powers. Their origins are less clear in the folklore, being variously dead, or some form of demon, or a species completely independent of humans or angels.