It is characterized by the smell of wet carpet, walls with a monochromatic tone of yellow, and buzzing fluorescent lights. Although Internet users have expanded upon this concept by creating different "levels" and "entities" of the Backrooms, the original version came from a two-paragraph 4chan comment on a post asking for "unsettling images", where an anonymous user invented a story based on one of the photos. The Backrooms drew comparisons to various other horror trends and media, including the photography of liminal spaces, the collaboration of the SCP Foundation, and the six-hour-long album series Everywhere at the End of Time.