In Marvel Comics, there's one concept that all writers share
That is, a single timeline branches into an infinite number of branched timelines, with infinite possibilities at every moment
The timelines are centered on Earth-616, the Prime Marvel Universe.
an infinite number of parallel universes that are branches of the Prime Marvel Universe, Earth-616.
Note that the MCU has also adopted the idea that there are an infinite number of unique timelines that do not branch off from the Prime Marvel Universe (616) and the Sacred Timeline (199999).
Since the branches of these unique timelines intertwine with the branches of the divine timeline, they are synthesized.
This is why the MCU's TVA is able to manage its own unique worlds that do not branch from the divine timeline.
Now that we have the general setup of Marvel's universe.
we can now begin to describe the external structure of the universe.
It's important to note that the external structure of Marvel's universe is mostly metaphorical in nature.
meaning that the Marvel Universe itself is the process by which the stories (works) are created.
First of all, I mentioned the interweaving of different branches when describing the universal setting.
There is a structure created by interweaving the branches.
As explained above, infinite branches are derived from one timeline.
And there are an infinite number of unique timelines that are not derived.
These unique timelines also have infinite branches.
There is a specific structure that is created by the interweaving of these different infinite branches.
Whoever projected this connected multiverse structure into a five-dimensional structure is the web of life and destiny.
It is important to note that the five-dimensional structure is simply a model (map) of the connections of the multiverse, not the multiverse itself.
If I remember correctly, the five-dimensional structure is a map created by Gaia's daughter when she saw the way the universes were intertwined.
However, I do recall that the terminology was sometimes used interchangeably, with the connected structure of the multiverse itself being referred to as the web of life and destiny.
And if you've read the Spider-Verse comics.
it is possible to manipulate this map to affect the multiverse.
Now let's talk about the metaphor of the web of life and destiny.
The Prime Marvel Universe (Earth-616) exists at the origin of the Web of Life and Destiny, as depicted in the comics.
Most canon events are derived from the Prime Marvel Universe (Earth-616) at the origin.
These canon events are designated by A(mazing)S(pider)M(an)# (the issue number in which they occurred)
In short, it's a kind of metaphor for the phenomenon where the original (Earth-616) is centered in the derivative works (parallel worlds) and the setting is reflected in the derivative works.
In some cases, the canon is taken straight from the source material, or the canon is applied to other characters as variations on the original art.
You may be wondering if the concept of canon events applies to MCUs.
The short answer is that in the MCU, we have virtually the same concepts as canon events: conflicts between different timelines in the larger multiverse, branches from different timelines intertwining, and key events happening in most timelines.
There's been some speculation among fans that the way the timeline in ATSV branches out like the branches of a tree has something to do with the MCU, which actually seems to be true based on the Blu-ray commentary for ATSV
For example, in X"97, when Beast explains that the Genosha incident is an absolute point in time.
instead of the What If It Happened One explanation, he says the exact same thing Miguel did.
Dr. Strange's path to becoming a sorcerer varies from one franchise to the next.
but there is a common thread that he loses something in a car accident and becomes a sorcerer.
That's the concept that the movie is currently adopting.