In order for a tattoo to be permanent, ink has to get into the dermis, the tissue just underneath the outer layer of your skin, called the epidermis.
This is done by making thousands of tiny pricks in the skin. To do that, a tattoo artist uses a handheld machine that has a needle affixed to it.
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Sports Fan Tattoos
Here's what's really happening to your skin when you get a tattoo
NEW YORK - APRIL 22: Brian Skidmore, fan of the St. Louis Rams shows off his Rams logo tattoo prior to the 2010 NFL Draft at Radio City Music Hall on April 22, 2010 in New York City. (Photo by Jeff Zelevansky/Getty Images)
OAKLAND, CA - MAY 20: An Oakland Athletics fan shows of his tattooed leg commemorating Dallas Braden perfect game during the game against the Athletics and Detroit Tigers at the Oakland Coliseum on May 20, 2010 in Oakland, California. The Tigers defeated the Athletics 5-2. (Photo by Michael Zagaris/Getty Images)
Colombian football fan Felipe Alvarez looks at the Atletico Nacional jersey tattoo --which he made in honor of footballer Andres Escobar-- during its making on October 9, 2010 at a studio in Medellin, Antioquia department, Colombia. AFP PHOTO/Raul ARBOLEDA (Photo credit should read RAUL ARBOLEDA/AFP/Getty Images)
PITTSBURGH - OCTOBER 07: A fan shows off his tattoo of Maxime Talbot #25 of the Pittsburgh Penguins during the game against the Philadelphia Flyers at the Consol Energy Center on October 7, 2010 in Pittsburgh, Pennsylvania. The Flyers defeated the Penguins 3-2. (Photo by Bruce Bennett/Getty Images)
25 May 2001: A fan of Shaquille O''Neal dared to tattoo 'I slept with Shaq' on his forehead. He received 2 floor seats from radio station Power 106 to game three of the western conference finals between the Los Angeles Lakers and the San Antonio Spurs at Staples Center in Los Angeles, California. DIGITAL IMAGE. Mandatory Credit: Donald Miralle/Allsport.
FORT WORTH, TX - APRIL 13: A Fan shows his NASCAR tatoo during the NASCAR Sprint Cup Series NRA 500 at Texas Motor Speedway on April 13, 2013 in Fort Worth, Texas. (Photo by Sean Gardner/NASCAR via Getty Images)
A Baltimore Ravens fan poses before the start of Super Bowl XLVII between the San Francisco 49ers and the Baltimore Ravens on February 3, 2013 at the Mercedes-Benz Superdome in New Orleans. AFP PHOTO/TIMOTHY A. CLARY (Photo credit should read TIMOTHY A. CLARY/AFP/Getty Images)
Parish priest Juan Gabriel Arias shows a tatoo depicting an image of Christ holding the Racing football Club shield at the parish church Natividad de Maria, which is also painted with the colors of the football team in Buenos Aires on November 27, 2014. The priest became member of the executive committee of the Racing Club after receiving authorization of Cardinal Jorge Bergoglio now Pope Francis. AFP PHOTO / Maxi Failla (Photo credit should read Maxi Failla/AFP/Getty Images)
A tattooed Brazilian supporter stands outside The Castelao Stadium in Fortaleza on June 17, 2014, ahead of the Group A football match between Brazil and Mexico during the 2014 FIFA World Cup. AFP PHOTO / YURI CORTEZ (Photo credit should read YURI CORTEZ/AFP/Getty Images)
LOUDON, NH - JULY 14: A race fan displays her tattoo during the NASCAR Sprint Cup Series Camping World RV Sales 301 at New Hampshire Motor Speedway on July 14, 2013 in Loudon, New Hampshire. (Photo by Patrick Smith/Getty Images)
WEST BROMWICH, UNITED KINGDOM - MARCH 15: A Leicester City fan shows his support to the club with a tattoo of his club during the Coca-Cola Championship match between West Bromwich Albion and Leicester City at the Hawthorns on March 15, 2008 in West Bromwich, England. (Photo by Matthew Lewis/Getty Images)
A fan of late Italian rider Marco Simoncelli shows her tatoo during the qualifying practice of the San Marino Moto Grand Prix on September 15, 2012 at the Misano world circuit in Missano Adriatico. Simoncelli died after an accident during the 2011 Malaysian Grand Prix at Sepang on 23 October 2011.
AFP PHOTO / GABRIEL BOUYS (Photo credit should read GABRIEL BOUYS/AFP/Getty Images)
OAKLAND, CA - OCTOBER 20: Oakland Raiders fans, including one with a full chest tatoo, watch warmups before he game with the Kansas City Chiefs on October 20, 2003 at Network Associates Coliseum in Oakland, California. (Photo by Stephen Dunn/Getty Images)
CHICAGO, IL - SEPTEMBER 2: Dallas Cowboys fan Tom Lundo (R) of Wooddale, Illinois, walks past a Chicago Bears fan outside Soldier Field in Chicago 02 September. Lundo sports a permanent tattoo of Dallas quarterback Troy Aikman roping former Bears quarterback Jim McMahon. (Photo credit should read TIM ZIELENBACH/AFP/Getty Images)
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The artist dips the needle in the ink, turns on the motor that moves the needle, and applies the moving needle to the skin.
The sharp needle pricks the skin quickly and repeatedly, dragging the ink clinging to it down into the dermis.
The tattoo needle is actually one piece of metal that has several ends to it.
A needle can have three ends or as many as 25. Each type of needle can achieve different effects. Needles with fewer ends are used for outlining, while needles with more ends can be used for shading or coloring.
Tattoo artist Leah Farrow told Smarter Every Day that the two most common machines are the rotary and the coil. The two different machines work differently but do essentially the same thing — moving the needle. The rotary machine's motor moves a rotating circular bar, which moves the needle up and down.
The coil machine uses a direct electrical current to move the needle. The tattoo artists steps on a foot pedal, which shoots a current into the coil, turning it an electromagnet.
The now magnetized coil pulls down the metal arm that's attached to the needle, which pushes the needle out. But as the metal arm touches the coil, another thin piece of metal loses contact with a circuit screw, breaking the current and causing the coil to lose its electromagnetic force.
The return spring pulls the metal arm back to its original place, pulling the thin piece of metal back into contact with the circuit screw and reconnecting the current that magnetizes the coil. This process happens over and over again as the tattoo artist holds the foot pedal down.
Smarter Everyday also got some macro lens to see the machines in slow motion action.
Seeing these tattoos in slow motion can undermine just how fast they work. According to a TED video,modern tattoo machines pierce the skin at a "frequency of 50 to 3,000 times per minute."
It wouldn't do much good to distribute the ink just on the epidermis because these outer skin cells are continually dying and sloughing off. The tattoo would disappear in just a few weeks. For tattoos to last a whole person's life, the machines have to pack enough punch to get the ink down into the dermis, the tissue just below the outer epidermis.
Some large ink particles are dispersed in the "gel-like matrix of the dermis," and others will be gobbled up by fibroblasts, a type of dermal cell that plays an important part in healing wounds.
Because tattooing is essentially making thousands of tiny wounds in the skin, the body's immune system goes into overdrive, sending special blood cells called macrophages to the site of the tattoo to engulf the foreign ink particles. This is part of the body's attempt to clean up and it's also the reason tattoos fade over time, but it also plays a part in making tattoos permanent.
Once a macrophage consume an ink particle, it goes back through the lymphatic highway and brings the consumed particles to the liver for excretion. But other macrophages don't make it back to the lymph nodes. Instead, these blood cells stay in the dermis, and the ink particles they've eaten continue to remain visible.