Art is about self expression. And hip-hop artists are no stranger to expressing themselves using all mediums available. Whether it's through music, dance or visual arts, rappers are professionals at making a statement when they walk into a room. And what better canvas to use than your own head?

It's incredible what rappers can think of doing to their hair. Some want their 'dos to be as expressive and colorful as their music. Some want to stand out from a crowd of music's new faces. While others just don't seem to care what's happening up there. Either way, they set themselves apart and set trends every time they debut a new look.

These eight rappers have had a particularly memorable track record of using their hair to stand out and show off their signature style. It's all been shaved, fried, dyed and braided to the side. And it's obvious that these MC's have no problem chopping it up on the mic or in the hair salon.

Below are some of rap's craziest hair transformation over the years.

Riff Raff

Before: Riff's signature look is tight braids and a sharp line-up.

The 55th Annual GRAMMY Awards - Arrivals
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After: Lately, the Neon Icon has been incorporating more color into is hair. Like these peachy blonde cornrows.

2014 MTV Video Music Awards - Red Carpet
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Wiz Khalifa

Before: Wiz started experimenting with color little by little.

BET's Rip The Runway 2011 - Arrivals
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After: Then he dyed his dreads purple and Twitter went crazy.

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Nicki Minaj

Before: When we were first introduced to Nicki, we knew her as the hard hitting Young Money MC who wigged out on stage.

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After: Blunt, sleek and sophisticated on the red carpet.

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Busta Rhymes

Before: In the late '90s, Busta rocked a palm tree worth of dreads.

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After: Nowadays, Busta wears his locks in a more manageable cut.

"Nas: Time Is Illmatic" New York Premiere
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Andre 3000

Before: Back in the day, it was all about keeping it crazy, free and flowy for Andre 3000.

Andre 3000 of Outkast
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After: Dre rocked a wacky wig for Outkast's festival tour this past summer.

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Coolio

Before: Coolio's always been known for his graffiti-defying 'dos.

Source Hip Hop Music Awards 2000
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After: Shaving and tattooing his skull is the latest look.

Big Brother 11 Final And Launch Of Ultimate Big Brother
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Kanye West

Before: When Yeezy was starting out, he was a little scruffy but all smiles.

MTV TRL With J-Kwon And Kanye West
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After: Now that he's a megastar, Ye constantly sets trends and keeps it moving...without smiling.

Lanvin: Front Row - Paris Fashion Week Womenswear Spring/Summer 2015
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Related: 50 Cent Gives Advice To Wiz Khalife About His Purple Hair
7 Of Kanye West's Worst Hair Cuts
7 Hot Hip-Hop Celebs Before And After Plastic Surgery

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