This was a messy year for pop music. Rules changed, hits were eccentric, and the whole twelve-month period felt enigmatic in a way we don’t usually expect from something as conventional as pop.

Pop stars—save for a guy named Aubrey and a girl named Ariana—were no longer the de-facto agenda-setters for a mass audience. And with the very definition of “pop star” and “mass audience” in flux, most music this year seemed to exist only in silos, playing loudly to a small subset of the population and lacking the universal quality we expect from pop trends. Yes, the whole world leapt perilously from their cars for the “In My Feelings” challenge—but that was the exception, not the rule. Overall, 2018 lacked big, unifying pop moments and an easily definable musical identity.

But this year also felt like the wobbly beginnings of something exciting and fresh. After Billboard finalized changes to its chart metrics in May, new artists and big hits could arise from anywhere—YouTube, Spotify playlists—and go directly to the top of the charts without ever needing a radio spin. Marquee acts like J. Cole let fans choose their singles, dropping surprise albums with no advance tracks, then servicing the most-streamed tracks to radio. Meanwhile, former unknown rapper Sheck Wes’s “Mo Bamba”—inconspicuously uploaded to Spotify over 18 months ago—meandered its way to the year’s most surprising top 10 track on the sheer power of word of mouth and streams.

And while a hit’s influence may have been more targeted than in years past, this longer tail of popular-music culture afforded some atypical starlets to emerge (take Tekashi 6ix9ine), strange songs to reach prominence (Travis Scott’s amorphous smash “Sicko Mode”), and a broader array of artists to find their specific niche (pop oddball Charli XCX and country hippie Kacey Musgraves, among others).

Indeed, the pop rule book was an open document this year. Here are some of the emerging new rules for pop during a highly transitional 2018:

For decades, hip-hop has played an outsize role in influencing American popular music—but it may have never been more evident, at least on the pop charts, than in 2018. Of the 49 weeks clocked by Billboard so far this year, 43 featured either a rap song or a song with a rap at No. 1, continuing a trend line of the genre’s increased centrality in mainstream pop. (In 2017, it was 33 weeks; in 2016, 31.) And, largely unprecedented, the six biggest debut album-sales weeks of 2018 all came from rappers: Drake, Travis Scott, Lil Wayne, Post Malone, Eminem, and J. Cole.

Much of this was driven both by ongoing changes in consumption habits, as well as some continued cultural shifts. Billboard’s altered metrics gave more weight to streaming, a space where a younger generation who grew up on hip-hop have the most influence, and where it’s by far the most popular genre.

Some fantastically bizarre success stories emerged as a result: Wes’s aforementioned brash “Mo Bamba”, XXXTentacion’s emo lament “Sad!,” and Kodak Black’s zany “Zeze,” all previously implausible crossover pop smashes, broke into the top 10. Cardi B’s song of summer, “I Like It,” was rapped primarily in Spanish, while Childish Gambino’s “This Is America” rose to No. 1 largely on the strength of its eloquent video addressing police shootings of unarmed black men. And one of the year’s most intriguing hits, Scott’s “Sicko Mode (feat. Drake),” was completely non-traditional in structure, split into three distinct movements, smash-cutting into one another with no central hook to speak of.

Some of these wholly redefined what constitutes a “hit.” It was exciting to see a song like “Mo Bamba,” which found its legs primarily through word of mouth and influential Spotify playlists like “RapCaviar,” reach No. 6 on the pop charts, thanks to the new chart metrics. Yet it lacked top 40 radio play—and thus the all-encompassing, inescapable, grocery-store aisle omnipresence once intrinsic to a top 10 record. Others, like the ubiquitous “Sicko Mode,” proved the power of streaming to redefine what a pop smash can sound like. At year’s end, it’s clear that most of the exciting (and popular) stuff that happened in pop music in 2018 actually happened in hip-hop.

While hip-hop dominated pop charts this year, actual pop music was not very, well, popular.

The unlikely poster child for this is Robyn, who returned this year with her masterful sixth album Honey. When Robyn dropped her pair of classic albums, 2008’s self-titled and 2010’s Body Talk series, she was a curiosity: critically adored, indie-approved, and a total hook machine whose choruses easily rivaled Katy Perry and Lady Gaga’s smashes of that era. But for whatever reason, Robyn could never quite cross over into superstardom.

In the years since, however, Robyn’s influential, just-left-of-center pop aimed at a small, devoted following has proven the blueprint for a new generation of pseudo pop starlets who can’t get their obvious radio smashes on the radio and don’t seem to care.

Troye Sivan’s “My My My!” was one of the best straight-ahead pop singles of the year, yet it peaked at No. 80 on the Hot 100. Likewise for Carly Rae Jepsen’s “Party for One,” Kim Petras’s “Heart to Break,” Allie X’s “Girl of the Year,” Kacey Musgraves “High Horse,” MNEK’s “Body,” and almost every song from Charlie Puth’s wonderful second album, Voicenotes. Robyn’s most obvious heir apparent, Charli XCX, followed her late ’17 electro-freak-show masterpiece Pop 2 with a slew of more centrist, alternate-universe smashes: “No Angel,” “Focus,” and, the best Britney Spears single that never was, “Girls Night Out.” None of them charted.

While these tracks might have, at one time, heralded a rising generation of pop superstars, they’ve shown that most pop artists now either choose, or are forced into, the Robyn approach: peddling to a narrow but fanatical cult fan base, and doing just fine that way. Both Sivan and Puth launched sold-out tours that played in large theaters across North America, while Petras, Jepsen, and XCX sustain careers by appealing to the exact circles that made Robyn a cult hero a decade ago (namely gay men and the Pitchfork crowd), where they are received as mega-stars.

As for Robyn herself? Without a lick of commercial attention, stans and social media made the release of Honey into what felt like a major pop event. And last month, Robyn announced a show at Madison Square Garden, a 20,000-seat venue usually reserved for multi-platinum, chart-topping stars, despite not having appeared on the Hot 100 since 1997.

Centrist pop still broke through in fits and starts (See: Zedd & Maren Morris’s “The Middle” or Camila Cabello’s “Never Be the Same”), but the genre overall this year mostly eschewed it’s milquetoast, radio-friendly identity for one more closely resembling a vital, underground subgenre.

Throw out everything I laid out above for two artists who broke the rules of 2018 by having Big, Banner Pop-Star Moments.

Drake devoured the entire pop ecosystem with his album Scorpion, and its attendant singles: “God’s Plan,” “Nice for What,” and “In My Feelings.” These were three of the biggest songs of the year which, combined, spent more than 50 percent of the year at No. 1 on the Hot 100.

Drake’s all-encompassing musical approach, one that essentially sucks up all genres and styles in its path and spits them back out in perfect pop packages, reached its zenith with tracks like “Feelings.” There, he nicked the aggressive, markedly queer New Orleans hip-hop subgenre known as bounce, and churned it into the sweetest, catchiest, love song of the year. “Feelings” then rode a meme (and placement on many Spotify playlists) to its inevitable place as the year’s signature song, and one of the only ones with the everywhere-ness of an old-fashioned pop hit.

Ariana Grande, meanwhile, completed her relatively slow ascent from starlet to the generation’s premiere female hitmaker with Sweetener, her most dynamic record yet. There, she balanced wonky R&B and hip-hop production courtesy of Pharrell Williams with more straightforward pop tracks from Max Martin, and bucked prevailing headwinds to succeed as a more traditional pop star.

And while Grande’s triumph in an ecosystem that appears hostile to more classical pop performers is somewhat inscrutable, her massive pipes along with her fluid alliance with hip-hop and R&B sounds set her apart. Songs like Sweetener’s title track featured production and vocal cadences that could easily suit a rapper like Lil Uzi Vert, while singles like “God Is a Woman” and “Thank U, Next” aped prevailing hip-hop and R&B sounds ably enough to fit a wide variety of streaming playlists that feature the more fashionable sounds of contemporary rap. Her tabloid and Instagram-conquering whirlwind engagement to S.N.L.’s Pete Davidson certainly didn’t hurt either.

While Drake and Grande were able to capture some old-school superstar magic, some standbys, once too big to fail, struggled to connect with their new material.

Beyoncé and Jay-Z finally released their long-rumored collaborative album, Everything Is Love, a celebratory capstone to their marital-strife trilogy that began with Jay’s 4:44 and Beyoncé’s Lemonade. Despite a massive stadium tour and E.I.L being a critical fave, it made very little commercial impact, debuting at No. 2 behind (seriously) a 5 Seconds of Summer album and producing no top 10 hits. Similarly, Taylor Swift continued to float numerous singles from late 2017’s Reputation—only one charted in the top 10—and Justin Timberlake’s Man of the Woods, despite his prime placement as the Super Bowl halftime performer, couldn’t find its feet.

Meanwhile, Mariah Carey dropped her best album in years, Caution, which showcased both her influence on contemporary sounds and panache for avoiding ill-fitting trend-hopping. Nicki Minaj had a spotty album with Queen that nonetheless featured the fierce single, “Chun-Li.” And Lady Gaga did some of her best work in recent memory on the A Star Is Born soundtrack.

While each of these veterans may have found love with their core audiences, none—save Gaga, who will likely win at least one Oscar—were able to capture the pop conversation or the series of multi-format hits, which were once their bread and butter. And while Kanye West successfully hijacked the Twitterverse with his MAGA hat and bizarre stream-of-consciousness interviews, his album Ye, released in early summer, came and went like a wisp of Wyoming campfire smoke.

R&B Is Up Next

Finally, and perhaps a bellwether of what to expect in 2019, a great surprise this year was the success of Ella Mai’s 90s R&B homage “Boo’d Up,” a track that bubbled under for almost a year before finally catching on. While R&B has struggled to get a foothold in the zeitgeist in recent years, Mai’s hit seems to portend the genre’s possible re-entrenchment in the mainstream. It also felt of a piece with a broader R&B movement, which this year featured the Internet’s uniformly excellent fourth album, the hazy, offbeat Hive Mind, Jorja Smith’s intoxicating Lost & Found, and Jeremih and Ty Dolla $ign’s extraordinarily fun collaborative effort, MihTy.

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