Out of Universe Description
The Origin is a pillar that is estimated to be a kilometer in diameter. The Origin is the location at which all reference points are determined by. Locations closer to the Origin are easier to get to than to location further from the Origin, though this can't be proved in universe due to the natures of the Backrooms, this is observable. Theoretically, an instance of the Backrooms is infinite, because of this nature, only a finite amount of Sectors are discovered and explored.
Some claim that once you go a certain distance from the Origin, you can never come back. The opposite of the event horizon of a blackhole. This is conjecture, never has been observed, and is passed around as a rumor.
Surrounding the perimeter of the Origin is a meter gap in the Backrooms, leading to a potentially infinite fall, and/or climb. Thus, the Origin is assumed to be infinite in height. It is unclear how the Origin stays in place without falling. Many people rumor that the base of the Origin is the Frontrooms, and is the only exit to the Backrooms. Even if this is true, it would be impossible to make the near-infinite descent to the base of the Origin. Another rumor, one that is more commonly believed, is that the Origin, being the center of the Backrooms, supernaturally props up the Backrooms, and gives structure to this. This is the popular belief, and for the most part assumed by the MEG.
The Origin is made of a metal similar to indium, but with strange properties. Like indium, it does not crack or break, instead it can almost stretch and squeeze. Tools can penetrate the surface of the Origin. Unlike indium though, the material of the Origin is much, much stronger, though it does have those properties. Also, the Origin has self-recovering properties. If it is dented, scratched, or if material is removed, it will quickly (varying in time but around an hour or more) regenerate into a perfectly smooth and reflective surface, of that silvery metal like indium. Nobody knows why the Origin is made out of this material, or what significance it has.
Some people assume that it is made of this material specifically so it's easier to climb. It's easy to see why this is plausible, as this material can be dug into with equipment similar to ice climbing equipment. It has a low tensile strength, and a high compressive strength. This allows it to be easily deformed with a quick impact, but can hold its ground on longer, heavier forces.
Nobody knows if the Origin is hollow, or what could possibly be inside it. Nobody even knows why it exists. And nobody has dared scale it. Some people claim to have heard voices from above and below them when near the Origin, but it's so distant it can't be confirmed.
Instances of the Backrooms - or what could be considered layers - are stacked on top of each other, all with the same point of Origin at the center. These layers are stacked in a non-Euclidean fashion, as some levels don't have a ceiling, have multiple levels, or are simply so vast it's impossible to quantify how far apart these instances would have to be spread apart to work. Instead, each instance of the Backrooms is stacked with about a kilometer in between.
AA follows a single instance of the Backrooms, and although other instances of the Backrooms are considered, and explored upon, it doesn't, and never will, take focus. When someone enters the Backrooms, it's assumed that which instance they enter is entirely random, and the place they enter is in some instance of Level 0, somewhere close to the Origin. If not finding another level, the Origin is the first landmark that most wanderers see, and therefore respect it as a point of reference.
Weird things and Mysteries to Explore.
Why is the Origin made out of the material it is?
Specifically because it's easier, and possible, to climb. There is no deeper reasoning behind it, well really it's all alluding to some kind of higher beings. Someone that designed it to be this way. People of AA will only be able to grasp this fact once they start to put together pieces of this strange puzzle: why everything almost seemed designed for them to escape.
Why is the Origin so big/tall?
The origin is its size to hold up the Backrooms, and to make escape from one instance to another more challenging. Like said before, still possible. Everything was designed with possibilities in mind. People of AA simply assume this is the case from the beginning, or well, only the first part. Nobody will truly realize the second part once another instance is reached.
Why are there different instances of the Backrooms? What differences are there?
There are different instances of the Backrooms to make up for the fact that the "event horizon" of instances exist, and that instances are built strictly at one, consistent, level. There are a few differences in the different instances of the Backrooms. 1) layout of levels, 2) the people and groups, and 3) the events, and history, along with the state of levels and entities. People of AA likely won't ever be able to figure this out, as travel from one instance to another is basically irreversible, and takes an (un)lucky noclip or scaling the Origin.
What is the purpose of the Origin? Why does it even exist?
The Origin was essentially the beginnings of the Backrooms, and is the z-axis for the Backrooms. It was created by God out of spite for the higher beings creating the event horizon. Humans of AA won't know how this happened, let alone why, until they start receiving messages from the higher beings.
What is at the base of the Origin? What is at the top?
Why is the Origin physically separated from the Backrooms? What holds them together?
Why is the Origin held with so much importance?
What is really beyond that "event horizon"?
Is the Origin hollow? If so, what's inside?
Why does all of this matter anyways? Why would anyone (including the readers) care? What purpose does the Origin serve for AA, and the stories told from it?
The Origin is something that every single person in the Backrooms has seen at least once. Without exception. It's a mysterious object created by some higher force, just like the entirety of the Backrooms, but the Origin itself is particularly odd. It's almost like the monolith(s) from 2001, a Space Odyssey. The Origin represents authority, the unknown, and the possibilities that the higher beings (that may or may not exist) have. It represents something permanent, and anchor point in the everchanging tide of humanity, the building point for all the civilizations of the Backrooms. But even though the Origin brings a sense of safety, and security of something absolute, it also gives a sense of fear. Nobody knows what it is, or why it exists. Nobody knows who made it, and for what purpose. Nobody can say how it affects them. Just like the monolith(s), the Origin is something absolute, yet something that will never be understood. The Origin is the unknown, an absolute barrier for humanity, seperating them from becoming a higher being.
The Origin's page is a message from inside. It's a warning from the higher beings.
