20. One Direction, "Story of My Life"
Sure, it sounds like Mumford & Sons, but "Story of My Life" finds 1D nailing the folk-pop genre with genuinely affecting emotion.
19. B2K feat. P. Diddy, "Bump Bump Bump"
Before Omarion was telling us what it's post to be, he was leading B2K and getting a P. Diddy assist on this slick chart-topper.
18. Backstreet Boys, "Everybody (Backstreet's Back)"
In a career full of mid-tempo love songs and heart-wrenching ballads, Backstreet Boys' signature, self-referential dance track endures.
17. Menudo, "Hold Me"
A joyous declaration of love: Menudo is shown leaping and twirling around in the "Hold Me" music video, and this song has made listeners want to do the same for decades.
16. 112, "Peaches & Cream"
Bad Boy R&B group 112 were given a magnetic piece of production with "Peaches & Cream," and expertly inject sex appeal into every corner.
15. 98 Degrees, "The Hardest Thing"
98 Degrees purists may opt for "Because of You," but "The Hardest Thing" represents the strongest distillation of the group's cheesy love lyrics and pinpoint harmonies.
14. The Wanted, "Glad You Came"
The Wanted's invasion of America ended hastily, but at least it included one undeniable club banger.
13. Boyz II Men, "End Of The Road"
Written and produced by Babyface, L.A. Reid and Daryl Simmons, Boyz II Men's "End of the Road" was the group's first huge ballad, and still their best utilization of the 'deep-voiced spoken-word breakdown' bridge.
12. LFO, "Summer Girls"
Even if you hated Billy Shakespeare and Abercrombie & Fitch, your heart would have to be pretty black to disregard the goofy charm of LFO's non sequiturs on "Summer Girls."
11. All-4-One, "I Swear"
All-4-One decided to turn a John Michael Montgomery country song into a boy band ballad in 1994, and soundtracked middle school dances for years to come.
10. *N SYNC, "Girlfriend"
It truly is a shame that "Girlfriend" proved to be *N SYNC's final single -- straddling the lines of pop, R&B and hip-hop, the song could have been the precursor to the boy band's stylistic shift, but instead proved to be the starting point for Justin Timberlake's solo career.
9. Take That, "Back For Good"
"Back For Good" is the essential Take That track for a reason: Gary Barlow's performance, defined by a gentle high note in the chorus and backed by the rest of the quintet, was never recreated quite as movingly.
8. O-Town, "All or Nothing"
After the world was finished snickering at "Liquid Dreams," O-Town recovered from that cornball single with an A-plus ballad that included an impossibly epic key change at its climax.
7. New Edition, "Candy Girl"
New Edition's "Candy Girl" hook stands as one of pop's most euphoric moments, and while the group's "Cool It Now" and "Mr. Telephone Man" were excellent follow-ups, they could never match the exuberance of their first single.
6. New Kids on the Block, "You Got It (The Right Stuff)"
"You Got It (The Right Stuff)" contains about five hooks that could all anchor a pretty great pop track if taken separately; instead, New Kids on the Block rolled them into one late-80's masterpiece.
5. One Direction, "What Makes You Beautiful"
One listen to "What Makes You Beautiful" was all it took to accept the inevitability of 1D Mania: the pitch-perfect power-pop track was as joyfully overwhelming as the hair-flips the U.K. lads sung about in the chorus.
4. Boyz II Men, "I'll Make Love To You"
"Close your eyes, make a wish, and blow out the candlelight," Boyz II Men's "I'll Make Love To You" begins; the R&B group probably never dreamt of having a baby-making song this timeless, but then, here we are.
3. *N SYNC, "Bye Bye Bye"
There's a reason why *N SYNC's No Strings Attached album scored the biggest opening sales week of all time: lead single "Bye Bye Bye" is an absolute monster of a lead single, with JC Chasez and Justin Timberlake leading the boys in a rhythmic, rollicking kiss-off.
2. Backstreet Boys, "I Want It That Way"
The best things in life are simple. "You are my fire/my one desire" is a couplet a third grader could write, but that's why it's the fulcrum for the defining track of the turn-of-the-century boy band boom. We never find out which way Backstreet Boys want it, but in the end, we want it that way, too.
1. The Jackson 5, "I Want You Back"
The boy band formula was perfected early on by the Jackson 5, who combined smooth moves, soaring harmonies and grinning bubblegum in ways that have been replicated for 45 years. "I Want You Back" is a love song aimed at young females, but it is also universal, including all listeners by hiding the heartache in a lip-smacking funk riff and seamless chord progression. "I Want You Back" is a towering pop treasure, and one that boy bands will always view as a blueprint to success.