NEW YORK — Matching mullets, regrettable tattoos, metal mouths and goofy grins.
Such long-lost looks were never meant to be seen by anyone except those flipping through the pages of an old family album or studying the photo frames on the fireplace mantel.
But now, Americans who grew up long before the Internet opened private lives to the world are digging up dusty boxes for photos to share on Facebook and other sites — sometimes to the chagrin of family members and schoolmates appearing in group shots.
Most people sharing photos from their past are simply having fun, and it can even serve as some form of collective healing.
"There's definitely a bit of exhibitionism involved," said Brandon Van Der Heide, an Ohio State University professor who studies the social implications of the Internet. "It's a way for people to connect to something that's familiar and laugh at themselves."
Nikki Smith, a 37-year-old Facebook user from Paducah, Ky., flipped through the scrapbooks she pieced together as a teenager and began scanning the old photos into her computer. The images took her back 20 years to the days of big hair, oversized sweaters, Air Jordan sneakers and aviator sunglasses.
"I had really, really bad hair in my senior year," Smith said. "But everyone knows. Everybody was there."
Smith said posting the photos on Facebook "gave everyone a good laugh."
It also put her back in touch with many of her old high school classmates. One photo, which shows Smith posing with her high school dance troupe in matching blue and white leotards and knee high boots, garnered more than 40 comments alone from other Facebook users.
"I don't think any of them are really awful," Smith said. "It was 20 years ago, who cares?"
But some people do care, especially when someone else has uploaded an unflattering photo or video.
Los Angeles screenwriter Mike Bender, who runs AwkwardFamilyPhotos.com devoted to such photos from the past, said a woman who shared a family photo later wrote to say that she was drunk when she submitted it and that her family was upset with her. Bender removed the picture immediately, but it was already all over the Internet.
What happens online can have a direct effect on someone's real life reputation, Van Der Heide said, yet people posting photos of others aren't giving them a chance to respond or control how they appear. He said unwarranted photos, videos or comments made about you could potentially "assassinate your credibility."
Online photos also have the "potential to hang around," getting copied and redistributed such that deleting your original might do little to erase the embarrassment, said Amanda Lenhart, senior research specialist at the Pew Internet and American Life Project.
Facebook does give users limited control over photos shared by their friends. Users can remove "tags" that identify them in individual photos, which would make it more difficult to find the photo in a search.
Facebook spokeswoman Malorie Lucich said users should "keep an open dialogue with their friends so they can discuss what type of photos they'd rather not see posted."
Bender, of AwkwardFamilyPhotos.com, suggests making sure everyone in the photo is in on the joke before posting something seemingly funny and harmless.
"We're not looking to humiliate anyone," Bender said. "We really want people to have fun with it."