The Backrooms began as a creepypasta post in 2019, describing endless, randomly segmented yellow office rooms you enter by no-clipping out of reality. The image and idea spread across Reddit, YouTube and TikTok as liminal space horror, inspiring games, short films and thousands of edits. Its signature fluorescent hum became shorthand for that empty, out-of-place feeling, so creators reuse the ambient sound whenever a scene should feel familiar yet deeply off, long after the original post.