Fox rang in its 25th year on TV Sunday night with a retrospective — hosted by Ryan Seacrest and featuring past stars Calista Flockhart, Ed O'Neill, and David Duchovny — that honored the network's most celebrated and boundary-pushing series. From Ally McBeal's miniskirts to The Simpsons' record-breaking run to the audacity of shows like The X-Files, Married… With Children, and Glee, Fox has clearly made a mark that can be seen all over TV today. Here, critics reflect on five ways Fox redefined broadcast television:

1. Fox proved the value of taking risks
"No network has ever been as consistent of a risk-taker as Fox has," says Price Peterson at The network fearlessly embraces odd, daring, and utterly original programming. Early in its run, for instance, Fox took a gamble on an unpopular sketch program — The Tracey Ullman Show — and we now have The Simpsons as a result. Some quirky but influential efforts, like The Ben Stiller Show and Greg the Bunny, weren't huge ratings winners but foreshadowed such experimental hits as Prison Break, Arrested Development, and Glee.

2. It paved the way for the truly modern family
Married… With Children was accused of appealing "toward the lowest common denominator," says Mike Hale at The New York Times. But the shamelessly crude sitcom's reputation as the anti-Cosby Show is precisely what lured blue-collar audiences, and its success heralded a new class of "dysfunctional-family sitcoms" that replaced the idealistic Cosby/Leave it to Beaver mold: Roseanne, Malcolm in the Middle, Everybody Loves Raymond, and, now, Modern Family and Raising Hope.  

3. Fox launched the reality TV craze
The network's longest-running show isn't The Simpsons, but the 23-year-old reality series COPS, a program that doesn't get enough credit for "spurring the reality TV revolution," says Lanford Beard at Entertainment Weekly. It's emblematic of the "kind of low-cost, high-profit equation" that all networks are now eager to replicate. Sure, Fox is responsible for despicable reality-TV offerings like Temptation Island and The Swan, but it also gave birth to one of TV's biggest gamechangers of the past decade: American Idol. That led to So You Think You Can Dance, Dancing With the Stars, The Voice, and so many more.

4. It taught TV execs how to win young audiences
When Fox launched, says Jill Serjeant at Reuters, young people "were bored with the cloned sitcoms and dramas offered by the major broadcasters." So Fox found its niche by offering youthful, boundary-pushing shows — The Simpsons, In Living Color and, later, Beverly Hills: 90210, The OC, and Glee. Airing such "outrageously cheeky fare, says Lynn Elber at Bloomberg Businessweek, proved the key to the "18-48-year-old audience that makes advertisers swoon."

5. Fox launched loads of future stars
We can thank Fox for "discovering future superstars like Johnny Depp and Jim Carrey," who first appeared, respectively, on 21 Jump Street and In Living Color, says Aly Semigran at Hollywood. Jennifer Lopez started as a Fly Girl dancer on In Living Color. The cast of the seminal hit Married… With Children "is still doing worthy work," says Beard. Ashton Kutcher and Mila Kunis got their starts on That '70s Show. And in addition to being unprecedentedly "frank and unapologetic about teen issues from special needs to sexual orientation and gender identity," Glee made Ryan Murphy a household name.