"머글" is a term derived from the Harry Potter series, created by J.K. Rowling. It refers to non-magical people who do not possess any magical abilities or knowledge of the wizarding world. In the context of the series, 머글 live in a world separate from wizards and witches, often unaware of the magical happenings around them. The concept of 머글 highlights the contrast between the magical and non-magical worlds. It serves to emphasize the uniqueness of the wizarding community and the challenges they face in coexisting with non-magical society. The term has since entered popular culture, often used humorously to describe anyone who is unaware of a particular subculture or interest.