The "Pixar Theory" states that all the movies from Pixar (from Toy Story to Monsters University) are all part of the same universe. They occupy one timeline and it shows how inanimate objects (toys to robots) and even animals conquer the world!

Sounds crazy? Given a chance, it actually makes a lot of sense. The Pixar Theory as we know it was devised by Jon Negroni, a blogger who occasionally writes for websites like What Culture. The idea was introduced in an episode of 'After Hours,' a short video feature series from Cracked.com. Negroni expounded on the idea with a more detailed explanation.

Negroni is quick to point out that this theory is not conclusive. From Jon Negroni.com: "The point of this theory is to have fun and exercise your imagination while simultaneously finding interesting connections between these fantastic movies. If you hate fun and/or imagination, you probably won't like this theory."

The bare essentials of the theory include:

1.      The timeline starts and ends with "Brave" and it also ends with "Brave." Of course, there are elements of time travel involved. One clue: The witch with the magic in "Brave" that caused Merida's mother into a bear is someone quite familiar.

2.      The next phase of the timeline is "The Incredibles." While it showed humans with superpowers, the villain in the movie introduced the concept of Artificial Intelligence fighting against humans. The concept of Zero Point energy, which somehow brings inanimate objects to life, is also introduced.

3.      The "Toy Story" trilogy shows how inanimate objects eventually gain life on their own. In "Toy Story 2" we also find some resentment among the toys. "Toy Story 3" also marks an appearance of BNL (Buy N Large) a company name recurring in Easter eggs all around Pixar movies.

4.      "Finding Nemo" and "Ratatouille" are examples of how the animals also gain sentience, but the humans are not aware of it yet (the surprise on Linguini's face).

5.      In "Up," Carl had to give up his house to BNL Corporation and also learns to communicate with animals. References point to humans polluting the Earth. According to pixartheory.com: "This is the start of the tipping point between animals and humans. Years later, the uprising between animals and humans begins."

6.      Far ahead into the future, "Cars" live on Earth where there are no more humans. "Cars 2" reinforces that with references to European and Japanese culture. Where are the humans?

7.      In "Wall-E" they are in a ship called Axiom. The humans are unwittingly controlled by machines. The film shows how the humans' uprising, taking the power back from the machines. Also, Axiom is owned and operated by a corporate monopoly: BNL.

8.      "A Bug's Life" shows how life on earth tries to re-establish itself.

9.      The explanation of "Monsters University" and "Monsters Inc." is that they are mutated animals/humans. When they travel through the doors, they are actually travelling to the past.

This is the reason why it is such a disaster for a human like Boo to return to Earth from the Monster world, which is actually just the future. Learning time travel enables her to unravel certain secrets, and also allows her to Scotland in the 14^th to 15^th Century..as the witch in "Brave."

The theory is reinforced by Easter eggs from the movies. The theory in full as well as the Easter eggs in question can be viewed here.