Credit: Neilson Barnard/ Getty Images Photo: One Direction on TODAY

British pop sensation One Direction sent tween girls into a frenzy when they performed live for the first time ever on The Today Show on Monday, March 12. But, if you are over the age of 14, you probably have no idea who these mop-topped, tight pants-wearing chaps are and why girls find them scream-worthy. Well, we’ve broken down everything that you need to know about the band.

There are five of them. Yes, we counted. The band is made up of Harry Styles, Niall Horan, Zayn Malik, Liam Payne, and Louis Tomlinson. They are from all over the UK and never met before forming their group. They are all under the age of 20.

Don’t embarrass yourself: call them 1D. Fans refer to the group as “1D” and you should too unless you want to be banished from the cool lunch table for being a total nerd.

They got their start on The X Factor (and owe some of their success to Nicole Scherzinger). In 2010 the five boys all competed as solo artists for the “Boys” category on the hit UK show. However, none of them were able to place in the category. Guest judge Nicole suggested that the five of them get together and compete in “Group” category and — bam — a boy super-group was formed. (Keep in mind this was before Nicole pissed off every X Factor fan in America when she essentially sent contestant Rachel Crow home.) The group placed third on the show and signed a contract with X Factor creator Simon Cowell’s record label, Syco Records.

Their boy band formula hearkens back to the days of N*Sync and the Backstreet Boys. Like the great boy bands of the early aughts, each boy in 1D represents a different “type” of boy, and who you like says a lot about you. Harry, with his wild hair and big grin, is the charming one who has dated a woman 15 years his senior. Niall, is the cute blond Irish one who loves to play guitar. Zayn is the dark and mysterious one who is British Pakistani. Liam is the mature one who suffered health problems as a child. Louis lives with Harry and is the funny, goofy one.

They do have girlfriends. Harry has dated thirtysomething British presenter Caroline Flack, who received death threats when the pair went public with their relationship. Zayn dated fellow X Factor contestant Rebecca Ferguson, who was 6 years his senior. Liam and Louis both have non-famous girlfriends.

They are going to take over America. 1D’s debut album, Up All Night, was released in the UK last year but it is being officially released in the States this week. The album is expected to debut at No. 1.

You’ve probably already heard their hit song, “What Makes You Beautiful.” If you’ve left your house in the past 6 months, you’ve probably already heard 1D’s smash hit song. In case you haven’t watch the official music video below.

Credit: YouTube Photo: One Direction, ''What Makes You Beautiful'' Music Video (VIDEO)

Want more 1D? Watch thousands of tween girls scream for joy as the band performs on The Today Show below.

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Credit: NBC Photo: One Direction Shuts Down Rockefeller Plaza While Performing on TODAY (VIDEO)

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