No matter how real they say they are, all of our favourite music maestros undergo something of a transformation before they achieve international fame.

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Footage of Green Day playing for students at their California High School in 1990 resurfaced last week, reminding us all that you’ve got to start somewhere.

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Inspired by the refreshing rawness of the punk rockers – who went onto superstardom thanks to albums like Dookie and American Idiot – here are 10 other artists who put in the hard yards.

Lady Gaga

Behold, Stefani Joanne Angelina Germanotta (aka Lady Gaga) on the piano. No meat frock, no huge spikes and no raunchy choreographed dance routines.

Recorded in late 2009 after she’d just signed her first record deal, Gaga treats an Italian-American event in New York to a pared-back rendition of a tune called Wonderful.

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One Direction

Television talent quests are often filled with staged excitement and mega hubris, but on UK’s The X Factor in 2010 one of the world’s biggest ever pop bands was formed.

Niall, Liam, Harry, Louis and (formerly) Zayne all auditioned individually, but at the ‘direction’ of judge and record mogul Simon Cowell the boys formed a band and the rest is literally history.

In the video below see all their auditions on the program, then formation – dominated by a series of underwhelming voices, pre-pubescent screams and finally their triumphant first group performance.

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Nirvana

The seminal American grunge rock band once played a show in front of no one at an electronics store, and there is video to prove it.

It happened in 1988 in their local Aberdeen in Washington, a year before their first album Bleach and three years before the world music changing Nevermind.

To be fair to the band, Kurt Cobain and co. don’t really look too different from later performances, such was the natural talent and always honest nature of the group’s work.

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Katy Perry

Is that Alanis Morissette or Katy Perry? Are you sure … because it look’s a lot like Morissette and a little (not much) like the girl who announced herself with I Kissed a Boy in 2008.

Truth be told, Perry used to be Katy Hudson, releasing a Christian rock-influenced record under the name in 2001 before switching to Perry in 2008. Watch the video if you too are finding this hard to fathom.

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U2

Before Bono was saving the world from everything that ever hurt it, his new band were being described on Irish television in 1978 as a heavy metal band with David Bowie influences.

In the clip the front man is only 18, but even then the critiquing panel comment on how their music seems to say something about the issues of the day – a space they came to own when they became famous all around the world.

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Lana Del Rey

Lana Del Rey was the fashionable damsel in distress that too many teenage kids had a crush on as soon as her self-titled 2010 album had been heard by indie-kids around the world.

But she used to be known at Lizzy Grant before she took on the mysterious stage name and that change, along with other alterations to her look, have been widely criticised and expanded on.

Take a look at the footage of her as Lizzy Grant and decide for yourselves whether she changed too much because of record company pressure.

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The Killers

They’ve played Wembley Stadium, Glastonbury, T in the Park, Coachella and Lollapolooza countless times over their 10-year career, all headed by the suave, designer label wearing front man Brandon Flowers.

But in 2002, two years before releasing smash album Hot Fuss, The Killers were still cutting their teeth on the diminutive Las Vegas rock scene, even playing in small gay and cross-dresser bars.

While they sound amazing in the video below, you would almost not recognise them on stage these days.

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Rihanna

At 15, there is footage of Rihanna taking the stage and belting out Mariah Carey classic Hero. She doesn’t really look too much younger than how she presents now, which is nice for her.

But it is certainly a more conservative set-up for the pop star which is understandable given her age. Just try not to think too hard about the fact that this is the girl who sings that “whips and chains excite me”.

The BDSM thing is surely a record company inspired move, how could anyone so innocent have such thoughts!?

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AC/DC

If you’re below the age of 30, have you ever had any of your baby boomer parents tell you they saw AC/DC at their high school? Have any of you actually ever believed them?

“Okay Mum and Dad, have another wine, suuurrrreeeeeee they did.”

Well, they did. And there is video to prove it.

AC/DC’s first two albums were only initially released in Australia and the lack of music sharing technology back then meant the youth of the 1970s had the rockers all to themselves.

Check it out here: ACDC in 1976 playing St Albans High School in Melbourne’s outer western suburbs.

Rage Against the Machine

At RATM’s first public performance in 1991 the first song they played was Killing In The Name Of. That’s like The Rolling Stones making their live debut with Satisfaction. Incredible to fathom.

The 53-minute show also features track Know Your Enemy, and notice how the show starts with one person in the crowd and by the end there are a flock of interested viewers enjoying the band and what would become Zach de la Rocha’s famous frenzied dancing.

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