2001: A Space Odyssey/WMG

The next stage in human evolution isn't the giant fetus, it's Artificial Intelligence.
While watching the film for the first time, I always thought that it was the Monolith that accelerated the evolution of AI, just like it accelerated the primates'. One thing that could support this theory that HAL, being a computer, revealed to be able to express emotions at the end. Sure, the 9000s are built quite long before the humans even discovered the Monolith, and are already proven to have a perfect track record. But having a perfect track record doesn't mean he also perfectly mimic the human mind. That deals with logic and analysis, but not feelings such as fear, suspiciousness and regret.

That's what also happened to the primates after the Monolith. Logically, they have no apparent reason to attack the other less intelligent group. The little battle seems completely intentional from their part, not of self defense, or quick insticts, or simple emotion. The human and AI mind might see to be pretty far in comparison, but consider, that they are at least built in our knowledge. The aliens however, would be completely different in nature, unlike those sci-fi characters that look and act surprisingly human, or at least, earth-like.

About the end scene, it's all about Dave, I guess. The HAL and AI plot are over, and now it's about him, and the Monolith.

The Aliens are speaking in excitement about Dave in the hotel room.
It is speculated that the strange gibberish echo-y voices that can heard in the hotel room are the aliens themselves speaking. They stop talking the moment Dave sees his older self eating because the experimental process has just started. So they've been quietly watching and analyzing as Dave gets older. They're either patiently watching as Dave ages naturally or accelerated the process to have him age quicker.

The SAL 9000 is the "twin-9000".
The "twin-9000" computer mentioned in the first film could very well be SAL 9000, unless there are other 9000 computers we haven't heard of.
 * This is confirmed by the 2010 novel.
 * It's confirmed in the 2001 novel. They tested their other two Earth-bound HAL 9000 computers to see if they would snap under the stress HAL did. They ended up proving the theory.
 * Yes, but Clarke didn't reveal that the computer was named SAL until 2010.

Contact (at least, the film version) is an alternate universe of 2001.
The mysterious aliens who built the Portal Network in the Vegan System are the creators of the Monoliths. The aliens who made contact with Earth are one of the many alien races that have evolved due to the Monoliths.

The Aliens created the rings of Saturn.
In the first book, there is a sentence which suggests that "no one had ever given the slightest thought to the curious coincidence that the rings of Saturn had been born at the same time as the human race."
 * The novel says this explicitly. The creation of the Monolith destroyed a moon. They say it outright.

It's not about aliens at all. Or not literally. It's about the nature of man.

 * And it does this by comparing us, successively, sort of in hierarchic progression, to other things, in a way that brings up all the biggest questions about us now. The first act is about the question of what, if anything, separates us from animals. The second act is about the question of what, if anything, truly and meaningfully separates us from machines. (Not a stretch considering it's Kubrick.) The final act is about the question of what separates humans from the divine.

The Starchild is a representation of the next stage in human evolution.

 * Over the course of the human race's evolution, we have become more infantile in proportions (neoteny is the technical term; chibi is the otaku term), which would explain the enormous space-fetus part. Tying into Clarke's Third Law is that people will become absurdly powerful by modern standards, explaining why it's an enormous space fetus. And, since the Monolith caused the first jump, it would also cause the second one, natch. Probably the most boring explanation for the ending ever, but meh. Also, read the book before you watch the movie: that way, the end is a hell of a lot less Mind-Screwy.

Moon is in the same universe as 2001: A Space Odessey.
GERTY is essentionly a nice version of HAL-9000. The cloning and technology seem similar as well.

The Aliens destroy or redirect everything headed beyond the Sol system
This explains the reason there is no 'Voyager 6' by 3001. Space technology is extremely advanced to the point where humans build space elevators and a ring around Earth made out of diamonds mined from Jupiter's/Lucifer's moons. They even terraform and colonize Ganymede. So why are there no interstellar colonies? Why was Frank Poole almost the first man to leave the solar system? Because interstellar space is as forbidden as Europa, of course! The monoliths have convinced the Aliens that humanity was omnicidal in nature, and need to keep humanity away from intelligent life. (By 3001, the aliens decide that humans are such maniacs that they need to be exterminated). So, Halman or possibly the Monolith pushes Frank Poole closer to the ship in the outer solar system, blows up robot probes when they pass the Oort Cloud, and haunts interstellar expeditions so that one crew member dooms the whole ship.
 * Yeah it sort of bugged me too that there are no human colonies further than Ganymede in 3001, even though Ganymede had already been colonized in 2061, meaning human migration must have just stopped for 900 years. There is a line in the book which says that humans had sent unmanned probes to all the stars within one hundred light-years. Maybe there's a prohibition similar to the one about landing on Europa, except in this case unmanned probes are OK, but manned ships are diverted. It might also explain why Frank Poole was still puttering around the Kuiper Belt, even though after a thousand years he should have been much farther out.
 * The reason humanity has no interstellar colonies by 3001 is simple. It is just.that.hard to colonize other stars. Remember that there is no FTL in the 3001 version of the Space Odyssey universe. Even the firstborn had to send a light-speed message in 2001 to a relay station 500 light years away, and wait 1000 years for the reply. Even having colonies in the Kuiper belt is actually only a tiny fraction of the entire solar system, which extends out to the Oort Cloud over 1 light year away from the sun. (Note that in 3001, it is never explicit that the Firstborn actually decide to exterminate humans. The humans just think/worry that this is the case, or that the malfunctioning monolith might just misinterpret any signal and become destructive anyways. The final line actually suggests that the Firstborn decided not to do anything to humanity.)

== HAL's murder of the astronauts was prompted not because he was trying to cover for a mistake he had made, but because the people running the mission had specifically programmed him to do so under certain circumstances. == This was a theory put forward by Rob Ager in his analysis of 2001. (Note his analysis covers the film only, not the book version.) The gist of the theory is this: HAL had been programmed to run subtle psychological tests on the crew all throughout the journey to Jupiter. If at any point, any or all of the crewmembers were determined to not be completely under HAL's psychological control, then HAL would have to dispose of them. HAL was sure that Frank was under his control because he had been able to beat him by cheating at chess. But Dave was a more skeptical sort, and when Dave insisted on double-checking the AE-35 unit instead of buying HAL's explanation of its failure, the crew's fate was sealed. HAL's "kill the crew" programming was then activated and he began carrying out his orders of exterminating everyone on the ship. (It may seem far-fetched that Mission Control would create a computer program that would result in the murder of an entire crew but this is a Kubrick film we're talking about. If you know anything about Kubrick's politics and other film works, it certainly wouldn't seem implausible to him that an Authoritarian Government Agency would casually terminate a crew on a mission as important as this one if it weren't completely certain of its control over them.)
 * But if Mission Control's top priority was maintaining HAL's authority over the crew, they wouldn't have told Dave and Frank that HAL was in error predicting the fault of the AE-35 unit.
 * . Bowman, by checking the replaced AE-35 unit and seeing that it was functional, already knew that HAL was in error. HAL's control over Bowman was lost at that point, regardless of what Mission Control would have said.
 * This kind of fails logic because, with the crew dead, who's going to carry out the actual mission? You've got who-knows-how-many-billions-of-dollars worth of space ship sitting there with nothing to do, now. Although one way to explain it is HAL was only supposed to kill one or two as a warning to the others, but someone didn't debug the code properly. Really, though, all it'd take is a quick call on the video phone: "Hi guys, how's it going? Food agreeing with you? By the way, fucking do exactly what HAL tells you without question or you're staying cooped up in there for the rest of your lives. Have a nice day." End of problem.
 * According to the theory, what Mission Control wanted was for HAL to have complete, subconscious, psychological control over the crew without the crew even knowing that it was under said control. The people running (what would be arguably) the most important mission in all of human history apparently thought that this type of strict psychological control over the crew was necessary, and they were willing to sacrifice an entire multi-billion dollar mission in order to ensure it went the way they wanted it to. (Note: at no point is Kubrick saying that the people in charge of this mission were acting in a normal, rational way. Rather, this scheme is the handiwork of an extremely paranoid, authoritarian government that only pretended to be normal on the surface--the type of conspiratorial government that Kubrick feared in real life.)

Dave believes that he sees God (literally) near the end of 2001.
"My God!" isn't used as an exclamation; it's used to identify the pronoun "it" in "My God- it's full of stars!" (For a not-so-serious example: "My chocolate- It's full of peanut butter!")

The Aliens are pre-mending planeswalkers
And the monolith are devices that allows the ignition of the Spark without the person dying.

It wasn't the use of clubs that the monolith introduced to the proto-hominids, but imagination.
Basic tool use was already something they were capable of, as with chimpanzees today. Mechanically, a club isn't that big a breakthrough. What was groundbreaking was the affected apes' ability to imagine the far-reaching opportunities that might follow from the use of an implement like the bone club, as illustrated by those shots of a warthog tapir collapsing as the skull was being smashed.

A Clockwork Orange takes place at the same time as 2001.
Both are Stanley Kubrick films that take place in the future. The year in A Clockwork Orange is never stated, and the events could be taking place on earth while Hal 9000 is going crazy.

My God - it's full of stars!