An old zen koan observes that we can never cross the same river twice. Because while the geography around it is solid and unchanging, the river itself is forever in motion. It may look the same on the surface, but the water we passed over yesterday is today miles downstream, while the water beneath us now could have come from anywhere -- rainfall, run-off, even another river.
It's worth keeping that model in mind when looking at how popular music evolved in the 1990s. Outwardly, things seemed fairly constant. There was nothing to alter the landscape as radically as the emergence of punk or rap did in the decades before. There were shifts in fashion, of course -- the rise and fall of grunge rock, the growth and decline of gangsta rap, the re-emergence of teen idols -- but these were gradual and expected.
But beneath the surface, the scene was one of constant flux. It seldom offered much in the way of drama. For instance, hip-hop listeners heard the bass-driven groove of Dr. Dre succeeded by the sample-based sound of Puff Daddy, which in turn gave way to the heavy beats of Master P. But these were not musical revolutions, just a change of players behind the scenes as the music rolled on.
But there were those who did make a difference. It may not have been immediately obvious, landing them atop the charts or on the covers of Spin and Rolling Stone, but there was no denying the impact. Somehow, these artists altered the currents of popular music, sometimes for the better, and sometimes not.
What follows is a look at the decade's 10 most significant pop artists, as well as its biggest technological breakthrough. This list shouldn't be taken as representing the best of the '90s, but rather of those who most memorably affected the mainstream's flow.
* Garth Brooks: Country's place on the pop charts was always a poor second to rock and soul. That changed in 1991, when Billboard adopted a computer- ized, point-of-purchase technology called Soundscan to compile its albums chart. Within months, Garth Brooks -- a phenomenon on the country scene but allegedly unknown to pop fans -- not only went to No. 1 with "Ropin' the Wind," but stayed there for 18 weeks.
Brooks was followed up the charts by country stars Clint Black, George Strait and Reba McEntire. But the predicted Nashville invasion never got more than a few artists wide, while Brooks' own crossover dreams evaporated with the spectacular failure of "Chris Gaines," his pop alter ego.
In a sense, Brooks' most lasting legacy may be his obsession with sales figures. In 1998, he went all out to ensure that his "Double Live" became the first album ever to sell 1 million copies in its debut week. Brooks made an act's chart position seem the equivalent of sports standings, but ended up hoist by his own petard when his record was shattered six months later by the Backstreet Boys' "Millennium."
* Nirvana: When "Nevermind" clambered to the top of the charts in early 1992, it was as if an alarm had gone off all across America, alerting teens and parents alike to the new wave of ennui sweeping popular culture. "Alternative" music partisans quickly claimed vindication, declaring 1992 "The Year Punk Broke," and for a while, Seattle's grunge aesthetic was all the rage.
But after Kurt Cobain's suicide in 1994, and President Clinton's denunciation of "heroin chic" a year later, grunge and the whiny, self-absorbed slacker lifestyle it represented were tossed aside. What remained was the notion that blunt, tuneful punk could be mainstream pop, a lesson Green Day, Blink 182 and others have taken to heart (not to mention the bank).
* The Internet: From DVD to MP3 to hard disc recording utilities like ProTools, digital technology opened many new frontiers in the '90s. But nothing changed the nature of the music business as dramatically as the rise of the Internet.
Don't believe the hype that MP3 -- a compression system that makes it relatively easy to download digital music files -- will destroy the recording industry. No, the slingshot most likely to bring down the major-label goliaths is the Web page, an easily accessed site that allows anyone, anywhere to hear a band's music or buy its CDs and merchandise. Because the Web eliminates problems of promotion and distribution that made bands dependent on major labels, it gives musicians the option of marketing themselves, significantly changing the industry's balance of power.
* Ace of Base: When Ace of Base made its American debut in 1993, the group was immediately compared to ABBA. Like ABBA, Ace of Base was also Swedish, had two women and two men, and dealt exclusively in frothy, blues-free Europop.