Dani (L) and Bella Thorne arrive at the 2016 American Music Awards in Los Angeles, California, U.S., November 20, 2016. (Photo by Danny Moloshok/Reuters)

Women lie in the sun in Domino Park as high temperatures hit the region in Brooklyn, New York, U.S., August 29, 2018. (Photo by Andrew Kelly/Reuters)

A model waits backstage before participating in AFI Joburg Fashion Week show with the theme #AfroAsia, in Johannesburg, South Africa October 4, 2018. Picture taken October 4, 2018. (Photo by Siphiwe Sibeko/Reuters)

A Hindu woman worships the Sun god in the waters of a lake during the religious festival of Chhath Puja in Agartala, India, November 13, 2018. (Photo by Jayanta Dey/Reuters)

Fishermen catch fish at Mao'er lake at the start of winter fishing season which is a local custom to welcome the new year on December 29, 2018 in Huaian, Jiangsu Province of China. (Photo by VCG/VCG via Getty Images)

In this October 27, 1983 file photo, soldiers brandish captured AK-47 rifles from the windows of a civilian vehicle as they drive near Point Salines Airport in St. George, Grenada. In 1983, U.S. forces invaded the Caribbean island of Grenada after accusing the government of allying itself with Communist Cuba. (Photo by Doug Jennings/AP Photo)

A model displays a creation from the Dolce&Gabbana Spring/Summer 2018 show at the Milan Fashion Week in Milan, Italy, September 24, 2017. (Photo by Alessandro Garofalo/Reuters)

Teenage girls are all steamed up these days about straight hair. The steam iron is replacing the huge rollers on which countless teens slept every night to achieve the height and curls fashionable until. The same girls endure having their hair stretched to absolute straightness on the ironing board, and then ironed to keep it that way. Unlike the roller setting, this takes teamwork. Gay Stilley, 14, goes through an ironing session with a couple of her friends at the Stilley Home in Glen Oaks, Queens, New York City on December 23, 1964. With a wary eye, Gay tries to watch the straightening process as one friend stretches her hair with a comb and another does the ironing, in the Stilley kitchen. (Photo by Marty Zimmerman/AP Photo)