Grant Morrison wrote and coordinated the DC One Million event. It was a company-wide crossover, a particular story encompassing the entire setting of stories taking place throughout an issue of each respective comic book magazine published by the company in the DC Comics line. It was the DC Universe crossover for 1998. Two things the otherwise-comprehensive everything2 entry does not mention is 1) how unusual it was for the time in that it actually centered around Superman and the Justice League of America.  Most of the crossovers at the time told us stories where the entire world was endangered and the universe on the brink destruction as the Devil was about to rule hell and earth and other odd stuff but the premiere super-hero team was not on the case.  It’s hard to explain in a non-comic-book sort of way.  2) The concept of Hypertime was introduced.  Reading through the entire crossover I noticed that some parts mentioned to have happened are not included in the story.

A whole lot of the story takes place off-camera: that is, in other comics. You have to read, as a bare minimum, three or four additional comics before many of the events referred to in comics after DC1M #1 begin to make sense. And those extra comics are patchy at best. While, in the core five, Morrison seems to be venting raw inspiration at full burn to make the DC Universe of 85,271 shiny and colourful as possible, the rest of the gaggle seem to be picking at his half-mentioned ideas (off-the-shelf superpowers, information as currency) and turning them into half-inspiring comics (Action Comics #1,000,000, Power Of Shazam #1,000,000 respectively). Maybe the secondary writers didn’t have the creative freedom they needed to keep the whole thing interesting, but the extra comics diluted the DC1M universe for me, rather than expanding on it… “JLA One Million” is the name of the trade paperback which collects this crossover. It contains nothing like the complete range of comics listed here: which is a good thing, as I said. Instead it limits itself to DC1M #1-4, JLA #1M, Starman #1M, Resurrection Man #1M and Man of Tomorrow #1M, with a few pages selected from each of Green Lantern #1M and Detective Comics #1M too. Overall I would say you do have a very good impression of the whole storyline in this TPB: all the salient details are present. It FEELS like there is a lot going on in the sidelines which you’re missing, but you’ll have to trust me when I say that this is just a product of Morrison’s high-paced writing, and what you’re missing is either inconsequential or missing from the crossover entirely (future Wonder Woman rescuing Supergirl, for example, doesn’t actually appear anywhere in the crossover).

I wish the Supergirl tie-in was a chapter of the story and not one of the theme issues. I don’t know if the writer, Peter David, was phoning it in or not. Overall the e2 guide is comprehensive enough and provides a better reading order than DC Comics did, if one is enterprising enough to get every comic book in the promotion.

In 1976 Marvel and DC Comics published their first inter-company crossover and the second co-publication between the two companies: Superman vs. the Amazing Spider-Man. Unlike DC One Million it was not wedged into the continuity of the respective comic book series and was likely set in a third universe, a third setting entirely.

The industry giants had collaborated once before, on an adaptation of MGM’s adaptation of The Wizard of Oz, but that comic had not involved their characters. Wizard was the trial run; for the American bicentennial, their best-selling heroes would meet.
Some comic-book crossovers present their characters as inhabitants of alternate universes; most DC/Marvel team-ups since have taken that approach. But for their first such comic (and a sizable number since), the characters simply share the same world, but have never met before… The comic features no advertisements, but boasts an assortment of extra features, including comments from head honchos Stan Lee and Carmine Infantino, one-page origins of Superman, Spider-man, Lex Luthor, and Doc Ock, and alternate cover concepts… A second treasury-size team-up appeared in 1981; it references this one. Later Marvel/DC team-ups would incline towards pairing Spider-man and Superman with characters more within their respective weight classes, and generally disregard this historic adventure.

The first meeting was published by DC and the second was published by Marvel Comics. The noted distinction between story-styles of the two is more or less correct:

What makes this approach interesting is the vast difference between Marvel and DC Comics at the time. In 1976, Marvel still retained most of its angsty, quasi-realistic 1960s tone (indeed, its characters were just starting to prolong their ages unrealistically), while DC’s ethos remained stubbornly in comicdom’s Silver Age.

What sticks out to me is an insight I have made before, mentioned before, but have rarely, well, never, seen elsewhere on the internet:

Superman uses his dual identity to protect those close to him; what good is that, when everyone knows the name of Superman’s girlfriend?

The idea that super-heroes have secret identities to protect the people closest to them is so old I cannot say where it originated. It would be fairly ironic if it came from a Superman comic book. For many characters it makes sense. The hero does not publicly associate with the same people in costume as he does when he lives his own life. But Clark Kent hangs out at the Daily Planet with Superman’s girlfriend and “Superman’s pal”. All his friends are publicly known to be friends or associates with Superman and in fact part of the backstory was that Clark Kent was the best friend of Superman. Elliot Maggin (among other writers) did explain in other stories that the main reason Superman kept the Clark Kent identity was not to protect his friends but simply to have a private life where people did not bug him as a celebrity.

 Between 1976 and 1998 Superman has changed a lot. Perhaps he has gotten to be a but more like Spider-Man, although the two still do not share the same weight class.