At the Billboard Music Awards in Las Vegas in May, the Top Social Artist was not one of the usual suspects such as singers Justin Bieber or Selena Gomez.

Instead, the fan-voted title went to a South Korean pop group named BTS.

That was only the beginning of the boyband's red-hot streak in the American music scene, as the seven-member group proceeded to make history: The first K-pop group to chart on the US Top 40 as well as perform on major platforms such as last month's American Music Awards.

They have also been appearing on popular talk shows such as The Late Late Show With James Corden, Jimmy Kimmel Live! and The Ellen DeGeneres Show.

The hosts have all expressed awe at both the group's talent and also at the intensity of the super fans who wait for them outside the studios.

In June, Time magazine named the band one of 25 most influential people on the Internet.

Given their huge exposure outside South Korea and even beyond Asia, BTS are now arguably the hottest K-pop act in the world.

Comprising members Jin, J-Hope, Rap Monster, Suga, Jimin, V and Jungkook, whose ages range between 20 and 25, the group, which made their debut in 2013, are known for their blend of hip-hop with rock and pop elements in hits such as Danger and Boy In Luv.

Most of the songs are written and produced by the band members themselves, which sets them apart from the typical K-pop group, whose members are merely singing and dancing puppets.

Clearly, there is a lot more to this boyband than just the usual good looks and slick dance moves.

The Sunday Times susses out the factors behind their immense global success.

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Why BTS are hot

SOCIAL MEDIA KINGS

Everything revolves around social media these days and BTS are kings of the social media game.

While it is common for celebrities to engage with their fans through Facebook and Instagram, BTS have made this a must-do in their daily lives. That means sharing everything from the usual music video clips to intimate videos of the members clowning about at birthday celebrations.

And unlike other boybands, which typically have separate accounts for each member, the BTS boys share a single account on each platform. It conveniently consolidates everything into one place for fans.

Such strategies are clearly working - their passionate fan base is responding in a major way. On Twitter, the band have amassed 10.9 million followers; on Instagram, they have 7.1 million followers.

Twitter's 2017 statistics report, released last week, saw BTS in top spot for not only being the most tweeted about music artist in the United States, but also in the world.

That is a feather in the cap for the group, who were named Top Social Artist at the Billboard Music Awards in the US in May, a fan-voted award handed out to the artist with the best social media engagement. They beat top American acts such as singers Justin Bieber and Selena Gomez.

BIG-NAME COLLABORATIONS

Thanks to notable collaborations with American artists, many international music fans got to know about BTS even if they were not clued in on the K-pop scene.

The latest is a remixed version of the BTS tune Mic Drop, with popular DJ Steve Aoki and rapper Desiigner getting in on the action.

The song was a huge hit from the get-go, debuting at No. 28 on the Billboard Hot 100 chart earlier this week, marking the first time a K-pop group has ever cracked the Top 40.

Only one other Korean act has ever bested this record - when singer Psy's viral phenomenon Gangnam Style peaked at No. 2 in 2012.

In a Billboard interview with Aoki last month, the DJ gushed about the group. He said: "These guys are the geniuses. They're so creative on every level - on their dance, on their sound, on their style, their flow, creatively musically, creatively on the fashion tip. They developed their own brand and they're global. It's incredible working with artists like that."

Earlier in March, American rapper Wale had released the politically charged song Change with BTS member RM, or Rap Monster. The song criticised "the alt-right" and "racist police", among other things.

In September, BTS teamed up with trendy DJ and producer duo The Chainsmokers on the song Best Of Me.

As a result of this partnership, The Chainsmokers vaulted back into the Top 10 of Billboard's Social 50, a list that ranks the most popular artists across various social media platforms.

This is noteworthy given that they had been out of the list for months at that point.

REAL HUMAN BEINGS

K-pop idols are known for being tightly controlled by their management - this is why they appear so polished all the time.

But fans and analysts say BTS are different - they come across as real human beings and not manufactured products.

Thanks to their constant social media updates of candid photos and live stream snippets of their daily lives, fans say the band feel "more accessible".

University student Claire Lim, 23, who has been a fan of BTS for the past two years, says: "I've been following K-pop for years, but BTS are the first group that made me feel like I understand the members' individual personalities and what they are really thinking."

These individual voices are also reflected in the band's songs, which are mostly written and produced by the members. The group are known for tackling political and social issues in their lyrics, which is pretty much unheard of for K-pop idols.

Am I Wrong, for example, condemns political apathy. The lyrics go: "If what you see on the news is nothing to you/If that comment is nothing to you/If that hatred is nothing to you/You're not normal, you're abnormal."

At a press conference to promote the band's latest EP, Love Yourself: Her, in September, BTS member Suga said: "It isn't a BTS album if there isn't a track criticising society."

Perhaps the management's holdis looser because the band's label is Big Hit Entertainment, a tiny outfit compared withmega K-pop music agencies such as S.M. Entertainment and YG Entertainment.

BTS facts

1 Their name is an acronym for the Korean expression, Bangtan Sonyeondan, which translates to "bulletproof boy scouts". In July, the band announced that the name would also stand for "beyond the scene".

2 Their fans are known collectively as Army, which stands for "Adorable Representative M.C for Youth".

3 Member Rap Monster, born Kim Nam Joon, is the international spokesman for the band as he is the only one fluent in English. He picked up the language from watching the sitcom Friends on DVD as a child.

4 They are the only K-pop act to have been given official Twitter emoji. One is a bulletproof vest and the other is the band's 2017 logo, which looks like a set of opened doors.

5 While known for their Korean songs, they also have two Japanese albums titled Wake Up (2014) and Youth (2016).