5 Things to Know About One Direction
PHOTO: Left to right; Louis Tomlinson, Niall Horan, Harry Styles, Liam Payne and Zayn Malik of One Direction perform on stage at The Roundhouse, Sept. 20, 2012 in London, United Kingdom.

Unless you're the parent of tweens -- or younger -- you may not know that there's a second British Invasion taking place, in the form of the new boy band One Direction.

That could soon change. The fivesome -- Harry Styles, Niall Horan, Zayn Malik, Liam Payne and Louis Tomlinson -- are proving that they are more than one-hit wonders. Their sophomore album, "Take Me Home," debuted at No. 1 on Billboard after selling over half a million copies its first week. That makes them the first British band to have both their first and second albums debut at No. 1.

Now, an older generation is taking notice. Barbara Walters named them on her Most Fascinating People List for 2012. They performed for Queen Elizabeth II at the 2012 Royal Variety Performance Monday night. And they've earned some serious cred from the royalty of British bands, the Rolling Stones.

"I watched a concert of One Direction on the TV the other night, you know just to check [it] out. It reminded me very much of our early concerts," Mick Jagger told CNN in a recent interview.

For those just getting up to speed on the group, here's a quick primer, complete with what teen fans are saying and what adults need to know.

The Band

In the era of "American Idol" and "The X Factor," great bands are no longer just born, they are made. A mere two years ago, the five teenagers met for the first time in the audition room of Britain's "X Factor." Individually, the boys failed to advance. Then, judge Nicole Scherzinger made the genius suggestion that they form a band during the bootcamp stage of the competition. Styles gave them the name One Direction, as in, there was only one direction they wanted to go -- to the top. The group ended up finishing third and was quickly signed to Simon Cowell's label. In March, they released their debut album, "Up All Night," which has sold 1.3 million copies and includes the single "What Makes You Beautiful." They also released a book and have a 3D movie in the works.

Harry Styles

Any tween will tell you, Harry Styles is the hottie of the group. The 18-year-old with the foppish curls has admitted to flirting with fans in the past. Much to their dismay, he dated the much older British TV host Caroline Flack, 32, who was subjected to death threats from Styles' young fans. "I'm surprised -- it's tough. I didn't kill someone, I just went out with someone younger," Flack told Look magazine in August. Since their breakup in January, Styles' lothario reputation has grown with reports linking him to Taylor Swift and Burberry model Cara Delevingne. "We do the same things every other lad our age does. We go out, we have fun, we meet girls and stuff like that," Styles told The Associated Press recently. "Sometimes it gets written about, which, yeah, we think about it and it's absolutely crazy."

This isn't Styles' first time in a band. Before One Direction, he was lead singer of a group called White Eskimo.

Niall Horan

If the sale of Niall dolls is any indication, Niall Horan is quickly becoming more popular than Styles. Perhaps it's Horan's Irish charm, which has put him ahead of Styles in the sales of dolls made in the band's likeness. But fans may be disappointed to learn that the 19-year-old has been spotted recently canoodling with a 20-year-old college student, Amy Green.

"We're still young, but we've passed the initial teenage years," Horan told AP earlier this week. "We've grown up quite quick in the job we have to do and we became a lot more independent."

Liam Payne

The word on Liam Payne, 19, is that he's the shy guy of the group. As a child he had to literally be pushed onto the stage, though he overcame his fears at 14 to audition for "X Factor" in 2008. Cowell told him to come back in two years, which, of course, he did.

After breaking up with his girlfriend of two years, Payne wasn't shy on Twitter about his crush on previous "X Factor" winner Leona Lewis, despite their eight-year age difference. The pair are now dating and Lewis, 27, recently opened up to Look magazine about their romance: "You'd be surprised how much we have in common. He's great. We see each other when we can."

Zayn Malik

Zayn Malik may look like the group's bad boy with his streaked coif, heavily tattooed arms and guy eyeliner, but he has no problem praising his girlfriend, Perrie Edwards of the British girl group Little Mix. Malik, 19, tells the latest issue of Britain's Cosmo that Edwards has helped him become the man he is today.

"Yes, I'm a big believer in the motto, 'Behind every great man there's a great woman.' And she's great," he said.

Louis Tomlinson

When it comes to love, Louis Tomlinson has the reputation of being the steadiest of the group. Styles reportedly set him up on a date with model and student Eleanor Calder last year, and on Saturday the pair celebrated one year together. "What a great year together @EleanorJCalder. Love you!!!!" Tomlinson tweeted. He told the latest issue of Britain's Cosmo that trust is what's kept them together. "We both trust each other -- I spend a lot of time out of the country on tour. She often flies out so I see her a lot. I think the key to a good relationship is being best friends too," he said.

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