THIS PAGE AND COVER: PHOTOGRAPHS FOR TIME BY KWAKU ALSTON; STYLING BY LISA MOSKO; MAKEUP BY ANITA GIBSON; HAIR BY VERONICA FLETCHER

Music mixes with memory. As we think back over the 20th century, every decade has a melody, a rhythm, a sound track. The years and the sounds bleed together as we scan through them in our recollections, a car radio searching for a clear station. The century starts off blue: Robert Johnson selling his soul to the devil at the crossroads. Then the jazz age: Louis Armstrong, Duke Ellington and, later on, Benny Goodman and "Strange fruit hanging from the poplar trees." Midcentury, things start to rock with Chuck Berry, "Wop-bop-a-loo-bop a-lop bam boom!" the Beatles, Aretha Franklin, "a hard rain's a-gonna fall," Bob Marley, Stevie Wonder. It might be better to forget the '80s--the posturing heavy-metal bands, Debbie Gibson, "Let's get physical--physical," the guy with the haircut in Flock of Seagulls. Perhaps the remembered sounds of R.E.M., U2 and Prince can drown them all out.

And how will we remember the last days of the '90s? Most likely, to the rough-hewn beat of rap. Just as F. Scott Fitzgerald lived in the jazz age, just as Dylan and Jimi Hendrix were among the rulers of the age of rock, it could be argued that we are living in the age of hip-hop. "Rock is old," says Russell Simmons, head of the hip-hop label Def Jam, which took in nearly $200 million in 1998. "It's old people's s____. The creative people who are great, who are talking about youth culture in a way that makes sense, happen to be rappers."

Consider the numbers. In 1998, for the first time ever, rap outsold what previously had been America's top-selling format, country music. Rap sold more than 81 million CDs, tapes and albums last year, compared with 72 million for country. Rap sales increased a stunning 31% from 1997 to 1998, in contrast to 2% gains for country, 6% for rock and 9% for the music industry overall. Boasts rapper Jay-Z, whose current album, Vol. 2...Hard Knock Life (Def Jam), has sold more than 3 million copies: "Hip-hop is the rebellious voice of the youth. It's what people want to hear."

Even if you're not into rap, hip-hop is all around you. It pulses from the films you watch (Seen a Will Smith movie lately?), the books you read (even Tom Wolfe peels off a few raps in his best-selling new novel), the fashion you wear (Tommy Hilfiger, FUBU). Some definitions are in order: rap is a form of rhythmic speaking in rhyme; hip-hop refers to the backing music for rap, which is often composed of a collage of excerpts, or "samples," from other songs; hip-hop also refers to the culture of rap. The two terms are nearly, but not completely, interchangeable.

Rap music was once called a fad, but it's now celebrating a 20th anniversary of sorts. The first hip-hop hit, Rapper's Delight by the Sugar Hill Gang, came out in 1979. Hip-hop got its start in black America, but now more than 70% of hip-hop albums are purchased by whites. In fact, a whole generation of kids--black, white, Latino, Asian--has grown up immersed in hip-hop. "I'm hip-hop every day," declares 28-year-old Marlon Irving, a black record-store employee in Portland, Ore. "I don't put on my hip-hop." Says Sean Fleming, a white 15-year-old from Canton, Ga.: "It's a totally different perspective, and I like that about it." Adds Katie Szopa, 22, a white page at NBC in New York City: "You do develop a sense of self through it. You listen and you say, 'Yeah, that's right.' "

Hip-hop represents a realignment of America's cultural aesthetics. Rap songs deliver the message, again and again, to keep it real. The poet Rainer Maria Rilke wrote that "a work of art is good if it has sprung from necessity." Rap is the music of necessity, of finding poetry in the colloquial, beauty in anger, and lyricism even in violence. Hip-hop, much as the blues and jazz did in past eras, has compelled young people of all races to search for excitement, artistic fulfillment and even a sense of identity by exploring the black underclass. "And I know because of [rapper] KRS-1," the white ska-rap singer Bradley Nowell of Sublime once sang in tribute to rap. Hip-hop has forced advertisers, filmmakers and writers to adopt "street" signifiers like cornrows and terms like player hater. Invisibility has been a long-standing metaphor for the status of blacks in America. "Don't see us/ but we see you," hip-hop band the Roots raps on a new song. Hip-hop has given invisibility a voice.

But what does that voice have to say?

Now tell me your philosophy

On exactly what an artist should be.

--Lauryn Hill, Superstar

It's a Friday night, early December 1998, and you're backstage at Saturday Night Live. You're hanging out in the dressing room with Lauryn Hill, who is sitting on the couch, flipping through a script. The 23-year-old rapper-singer-actress is the musical guest on this week's show. It's her coming-out party, the first live TV performance she's done since releasing her critically acclaimed and best-selling album The Miseducation of Lauryn Hill. She might also do a little acting on the show--SNL staff members have asked her to appear in a skit. But as Hill reads, her small rose-blossom lips wilt into a frown. She hands you the script. It's titled Pimp Chat--it's a sketch about a street hustler with a talk show. Hill's role: a 'ho. Or, if she's uncomfortable with that, she can play a female pimp. Hmmm. Now, being in an SNL sketch is a big opportunity--but this one might chip away at her image as a socially conscious artist. What's it going to be?