Television has changed so much in the 25 years since the FOX network launched in primetime — an anniversary(*) being celebrated with a primetime special on Sunday night — that it's hard to convey to someone under 30 what a big deal it was for a fourth network to not only debut, but endure.
 
(*) Technically, FOX launched in the fall of 1986 with Joan Rivers' "The Late Show." The anniversary being celebrated here seems to be of the primetime premiere, which was April 5, 1987.
 
Today, it seems like there's a new channel being launched every 30 seconds (usually in the 800s of your digital cable tier), but the TV universe in the spring of '87 was mainly about the Big Three broadcast networks. Cable was still something of a novelty, and if you had any independent broadcast stations in your area, they tended to show old movies and repeats, and/or have a signal so weak you'd have to put your TV antenna into your toaster to pick it up.
 
The DuMont Television Network had folded in 1956, and in the 30 years since, there were many attempts to launch a viable fourth network. A handful actually got on the air for a little bit before going away, but most of them — like Paramount's mid-'70s attempt to build a network around a new "Star Trek" series — were killed in the planning stage.
 
So when the Fox Broadcasting Company launched, it seemed simultaneously like a fool's errand and a big deal. There were only a couple of shows on that first April night — "Married... with Children" and "The Tracey Ullman Show" — with more being added until there was a full Sunday lineup, and then a Saturday lineup, and on and on. But the limited initial roster made it easy for a young TV nerd like me to keep track of all the network's shows for a while. I watched "Married," obviously (I was 13, and that show had both crude jokes and Christina Applegate), and "Tracey Ullman" (though mainly for those "Simpsons" shorts that aired in between the sketches), and "21 Jump Street," but also the ones that didn't endure like "Duet" or "The New Adventures of Beans Baxter," or "Second Chance."
 
After a while, some trends became clear, and the biggest one was that the most successful FOX shows — and usually, but not always, the best ones — tended to be ones that broke the mold, and that the more traditional ABC, CBS and NBC wouldn't have dared try.
 
At the start, there was "Married... with Children" being cited as evidence of the decline and fall of Western civilization: a family sitcom that didn't believe in hugs and tear-jerking and the rest of the false sentiment designed to make you forgive all the insults leading up to the "awww." Then there was "The Simpsons," which also started as an abomination — President Bush the first and his wife both condemned it in the early days — and is now an institution. There was "In Living Color," which showed that both "Saturday Night Live" and white actors shouldn't have a monopoly on sketch comedy.(**) "The X-Files" proved it was possible to have a commercially successful sci-fi show. For a couple of years, the quirky blend of legal drama, fantasy and music made "Ally McBeal" into a phenomenon. Etc., etc.
 
(**) For a while in the early-mid '90s, FOX made a concerted effort to program for African-American viewers, not only with "In Living Color," but the Thursday night bloc of "Martin," "Living Single" and "New York Undercover." As the network became more successful and mainstream, those shows dropped away, and would-be fifth networks UPN and the WB tried a similar strategy. Predictably, the WB (run by a lot of early FOX execs) also scrapped its minority-targeted shows once it began having success in other areas.  
 
Every now and then, FOX would have a more conventional hit, but even they seemed to come out of nowhere. "Beverly Hills 90210," for instance, debuted in a season with a half-dozen other high school series and was largely ignored by the media compared to the likes of "Hull High" and "Ferris Bueller." It wound up running 10 seasons, launching an iconic spin-off in "Melrose Place," and eventually a low-rated sequel series on the CW.
 
"The Simpsons" kept the spotlight on the network in the early days, and then the acquisition of NFL broadcast rights in 1993 — an expensive but necessary gambit that elevated FOX even as it damaged CBS (which in turn had to buy the other NFL package away  from NBC a few years later to become relevant again) — made it clear FOX wasn't going away.
 
And as the century changed, FOX's successes largely came from thinking outside the box. "24" and "American Idol" seem like obvious hits now, but both were greeted with tons of skepticism at the time. Before "Glee," the idea of a weekly musical seemed like a disaster-in-waiting (thanks in part to '90s failures like "Cop Rock" and the aforementioned "Hull High"), but FOX not only launched it successfully, but in an unconventional way.
 
Obviously, when you experiment that much, you'll fail, a lot. For every "X-Files," there are a few dozen sci-fi series that FOX canceled quickly, but they're still shows the network tried that their competitors never would. (For all the anger that "Firefly" fans have over how FOX scheduled the show, it wouldn't have gotten on the air at any other network.) 
 
The extraordinary popularity of "American Idol" has changed that game quite a bit, though. When you've been the highest-rated network on TV for as many years in a row as FOX has, you can't quite play the brash upstart anymore. There are more shows that, regardless of quality, feel like they could easily exist on another network, and more extensions of familiar faces (Gordon Ramsay) and creators (Seth MacFarlane). There are still some genuine experiments, like the delightfully weird "Bob's Burgers," but other times even the shows that are risky from one angle are very conservative from another, like the expensive time travel series "Terra Nova," which was designed as a big-tent series with something to appeal to everyone in your family.
 
While it's possible to create art that satisfies everyone, more often than not, that approach leads to something that's not especially satisfying for anyone. Most of FOX's successes — and the existence of the network itself — came not from a belief that everybody would watch, but that enough people would to make things both interesting and profitable.
 
As the anniversary special approached, I began thinking about my favorite FOX shows ever, and most of them qualify as ones I'm not sure the other networks would have tried — or, in some cases, as ones the other networks would have killed far, far more quickly.
 
Even if you haven't been watching FOX since night one, I'm sure you have some favorites of your own, whether series, individual episodes, weird moments, etc. So fire away in the comments.
 
Alan Sepinwall may be reached at sepinwall@hitfix.com