For those of you who may see the Wolverine movie, and kind of think movie Deadpool is cool, you should read this and discover how much cooler than movie Deadpool the real thing actually is.
Ten Things You Should Know About (Canon) Deadpool
1. Origin and Name Origin:
Deadpool's early origins are hazy. One popular version of his parents has his mother dying young of cancer and his military father trying to raise Wade, who acted out because he was upset about his mother's death. In this origin Wade's father is killed by Wade's friend in a barfight when he's trying to get Wade to come home or behave, and Wade leaves, joins the Special Forces, is kicked out for being, in his own words, "too good," and becomes a mercenary. Sometime after this he is diagnosed with cancer, and breaks off a relationship with his then-girlfriend (who later becomes the mutant Copycat) because he doesn't want her to have to deal with it. He joins Weapon X because they promise they can cure him.
To cure him they give him a strain of Wolverine's healing factor. It doesn't work, but he is assigned to a team of other recruits. He "ices out" of the program for killing another recruit (the implication is that the other recruit killed for fun instead of the job) and is sent to "The Hospice," which is supposed to care for the program rejects but is actually an awful place with a Mengele-like doctor who experiments on the patients.
Wade tries to kill himself on arrival, which is Frowned Upon, and the sadistic Attending and Dr. Killebrew indicate a "special interest" in Wade, which means his odds in the "dead pool," i.e. the betting pool of who will die first, go way up - he will not die for a long time if they want to experiment on him endlessly, because they won't let him. Thus he becomes "King of the Dead Pool". Eventually Wade is driven crazy by the torturous experiments and starts seeing the incarnation of Death, who falls in love with him (because he is living but can see her). She tells him to join her, and he starts trying to make the Attending kill him. He says outlandish things and heckles the Attending constantly, raising other patients' morale in a very Ken Keseyan way. The Attending finally gets angry enough to try to take control back by lobotomizing Wade's best friend in the Hospice. To put his friend out of his misery, Wade kills him. The rule is that an inmate who kills must be killed, so the Attending has finally gotten what he wants - to kill Wade. Wade and Death are fine with this, EXCEPT that Wade is now so mad about what happened to his friend that his desire for revenge kick starts his healing factor, which causes him to re-grow his heart after it's ripped out. He takes the name "Deadpool," kills the Attending, and sets all the Hospice rejects free before going back to his mercenary ways in a new uniform that hides his scarred physique.
2. The T-Ray Debate:
Just ignore any and all inferences that Deadpool is really a dude named Jack who killed T-Ray and took his identity as Wade Wilson. And accept that all storylines involving T-Ray and his weird desire for "revenge" are whacked. Seriously. Ignore.
3. Mutant Powers:
Deadpool is not a mutant. Deadpool is a mutate. I.e. he has a healing factor, but it is derived from Wolverine's DNA, not something he was born with. The healing factor is insanely powerful, which means not only has he, at times, regrown digits and limbs, but he's even completely regenerated from A HAND. he's also recovered from decapitation, once his head was replaced on his body. The growth rate depends on a lot of things, including his mood at the time. For instance, he regrew his heart extremely quickly because he was motivated by extreme anger and a desire for revenge. His healing factor also makes him immune to things like drink and poison, unless they are in extremely high doses. The Cat once put him out with a dart that had enough tranquilizer to down an elephant for an hour or something like that, and opined that it would keep Deadpool knocked out "not nearly long enough."
4. By-product of Mutant Powers:
Because Wade had cancer when his healing factor kicked in, he has scar tissue and tumors disfiguring his entire body from where the healing factor interacted with the cancer. The healing factor constantly regenerates his cells in order to keep the cancer at bay. An effect of the constant regeneration is that his brain cells are in a constant state of flux, leading to one of the main reasons why Deadpool is Awesome. The constant shifting makes Deadpool insane in his own very special way. Traits of his insanity include his wacky sense of black humor and interjections of pop culture inanities, an unpredictable fighting style that's allowed him to beat Taskmaster and many others, and the awareness that he is actually in a comic book. This means Deadpool breaks the fourth wall A LOT, usually with very funny results.
5. Fighting and Other Skills:
Deadpool is skilled in all sorts of weaponry and a variety of fighting styles, including mastery of many martial arts. His trademark weapons include two katanas, a variety of guns (often helpfully labeled with things like, "Deadpool's Gun" and "This End at Enemy") and grenades. That's not by any means the limit of his arsenal, though. He's skilled with explosives and all kinds of random things. He can also speak German, Japanese, and several other languages. He also uses, at various times, a teleporter that can get him out of (and into) trouble, and a holographic image inducer to change his appearance. In the official Marvel guides, Deadpool ranks evenly with Wolverine in everything except fighting skills (1 point less). He's actually ranked above in speed, due to being a teleporter.
6. Romantic Interests:
Deadpool's had a thing for Siryn of X-Force for a long time. It's been vaguely returned now and again, but never seriously because he is, after all, crazy. And ugly. He had a relationship with Copycat both before and after Weapon X. Death fell in love with him at one point, but Thanos was jealous and thus cursed Deadpool so he's basically immortal. And, of course, almost all 50 issues of Cable & Deadpool are one big bromance, with Hints of Hoyay, referred to by the writer as "the greatest romance I've ever written." Take from that what you will. Currently, he either has or is pretending to have a thing for Black Widow of the Thunderbolts.
7. Deadpool in Popular Culture:
Deadpool has his own page on TVTropes. Because he is awesome. It is FUN READING. Seriously, dive in and read it. You may never surface again.
8. Deadpool's Rep:
Deadpool is pretty much one of the best fighters in the Marvel Universe, and I'm not even just saying that because I love him. Taskmaster (who is a premiere trainer of mercenaries) has acknowledged that *everyone* knows how good he is (but sometimes won't hire him because he's so unpredictable/unprofessional). He's beaten Taskmaster twice. He's gone toe-to-toe with Wolverine, Iron Fist, and The Hulk. He's laid out an entire squad of fighters by shooting without actually even really looking at them. He's fought several superpowered people at once without breaking a sweat. He kicks ass and takes names, y'all. And is awesome all the while.
9. Times Deadpool Has Saved the World All By Himself:
Once, to date. But nobody really knows and he's ashamed of it. Seriously.
10. Times Deadpool Has Helped Others to Save the World:
At least once, but Norman Osborn took credit, that tool.
Three Things You Should Know About Movie Deadpool
1. The way Wade is portrayed up until Nigeria is completely acceptable in terms of canon. Fighting style, wisecracks, etc. All fine. Ryan Reynolds does a great job IMO.
2. The Wade that's portrayed post-"Weapon XI" is not even remotely canon except for the healing factor, nor is his name origin. See above.
3. FOX are idiots for having changed his origin. That is all.
OK, I'm tired. Anyone want to know other things about Deadpool? Remind me to post about them. Heh.