Compendium

Anemoia: Nostalgia for a time you never lived through.

The Astley Paradox: An internet joke about asking Rick Astley for the film Up and treating either possible answer as a broken promise from his best-known song.

The Backrooms: A fictional maze of seemingly endless rooms and corridors, often entered by slipping out of ordinary reality.

Boots Theory: Sam Vimes’s idea that people with less money upfront can end up paying more over time because they can only afford goods that need frequent replacement.

Byway: A smaller or less-traveled road, often away from a main route.

Cognitive Bias: A systematic tendency in thinking or judgment that can affect how people interpret information and make decisions.

Cognitive Dissonance: Psychological discomfort associated with holding conflicting beliefs or with acting in a way that conflicts with one’s beliefs.

Cognitive Economy: The use of mental categories or shortcuts to gain useful information while conserving limited attention and effort.

Collective Unconscious: Carl Jung’s proposed shared layer of the unconscious, containing inherited patterns he called archetypes.

Compendium: A concise collection of information about a subject or a range of subjects.

Creepypasta: A horror story that spreads online through copying, reposting, or retelling.

CSS: Cascading Style Sheets, the language used to control the presentation and layout of web content.

Deltarune: A role-playing game by Toby Fox that follows a group of characters through mysterious worlds, combining exploration, dialogue, and patterned battles.

Disney: The entertainment company and brand associated with animation, films, characters, and themed destinations such as Disneyland and Walt Disney World.

Disney World: Walt Disney World Resort, the Disney resort near Orlando, Florida, with four theme parks and a wider collection of hotels and experiences.

Disneyland (California): Disney’s original theme park in Anaheim, California, which opened in 1955.

Emoji: A pictorial symbol used in digital text to express an idea, object, reaction, or emotion.

Emoticon: An expression made from text characters, such as :-) or :-(, to suggest a face or convey a feeling.

Enshittification: Cory Doctorow’s term for the deterioration of a platform as its operators shift benefits away from users and partners toward extracting more value for themselves.

Expository Writing: Writing that explains, informs, or clarifies a subject through organized information and examples.

Felix Felicis: The luck-enhancing potion in Harry Potter, also known as Liquid Luck.

Forlornness: A feeling or appearance of loneliness, abandonment, or hopeless sadness.

Found Footage: A storytelling technique that presents a film as recordings recovered from within the story.

The Game: A mind game whose goal is to avoid thinking about the Game. Thinking about it counts as a loss, which players commonly announce.

Gift Economy: A system in which goods or services circulate through giving and social relationships, often with expectations of reciprocity.

Gordian Knot: An exceptionally difficult or tangled problem, named for the ancient story of Alexander the Great and an intricate knot.

Hagioptasia: A proposed psychological process in which a person, place, object, memory, or idea seems to possess an extraordinary significance of its own, whether enchanting, nostalgic, sacred, or uncanny.

Halloweekend: An informal name for a weekend of Halloween celebrations.

HTML: HyperText Markup Language, the language used to give web content its structure and meaning.

JavaScript: A programming language widely used to add behavior and interactivity to websites.

Kane Parsons: A filmmaker and visual-effects artist, known online as Kane Pixels, whose Backrooms videos turn familiar spaces into unsettling fictional environments.

Kenopsia: The eerie feeling of being somewhere that’s usually busy when everyone is gone.

Level 0: The familiar yellow-room setting that serves as the first area in many versions of the Backrooms. It is often called “The Lobby.”

Liminal Space: A place or state in between. In online photography and art, it often means a familiar place that feels strangely removed from its usual purpose.

Luminary: A person distinguished for their influence or achievements in a field. The word can also mean a source of light.

Marvin’s Friend: The Lifeform encountered by Marvin Leigh in Kane Pixels’s Backrooms - Pitfalls, later jokingly called “Marvin’s Friend” in the series.

Metanostalgia: Nostalgia for nostalgia itself, or longing for the way an experience once made you feel.

Multipotentialite: Someone who pursues several interests or creative paths, sometimes bringing them together in the same work.

Noclip: To pass through walls or floors that would normally block a player in a game. In Backrooms stories, it means slipping out of ordinary reality.

Nostalgia: A wistful, often bittersweet longing for the past.

Numinous: Evoking a sense of sacred or mysterious presence, often with awe.

OP (Original Poster): The person who started an online post or discussion thread.

OP (Overpowered): A description of a character, ability, item, or strategy whose power is unusually high compared with the challenge or its alternatives.

Philanthropy: Efforts to promote other people’s well-being or the public good, often through giving money, time, expertise, or other resources.

Pokédex: An encyclopedia within Pokémon games that records information about the Pokémon a Trainer encounters or catches.

Pokémon: A franchise about discovering, befriending, training, and battling creatures called Pokémon, spanning video games, cards, animation, and more.

Question-and-Answer Site: A website organized around people asking questions and receiving answers from other users.

Reality Distortion Field: A phrase associated with Steve Jobs for persuasive confidence that can reshape how other people judge what is possible.

SB-129: A SpongeBob SquarePants episode in which Squidward’s attempts to find peace take him through time and into a strangely empty space.

Sectumsempra: A harmful spell in Harry Potter that causes severe cuts to its target.

Specious: Superficially plausible, but actually wrong.

Spoonerism: A mix-up in which the opening sounds of two words exchange places, often producing a humorous phrase.

Static Front-End Website: A website whose pages are delivered as prepared files, with HTML, CSS, JavaScript, and other assets handling what visitors see and use.

Technical Writing: Writing that helps a particular audience understand a technical subject or complete a technical task.

Toby Fox: A game creator and composer best known for Undertale and Deltarune.

Torii: A traditional Japanese gate that marks an entrance or boundary associated with a Shinto shrine.

Undertale: A role-playing game by Toby Fox in which a human explores an underground world of monsters, with choices about fighting and showing mercy.

Worldbuilding: Creating a fictional setting and the details that make it feel like a place of its own, such as its geography, history, culture, or rules.

XP/EXP: Common abbreviations for experience points, a game resource used to measure progress and often advance a character’s level or abilities.