Yushan Ou of China competes on the balance beam at the Women's Team Final during the Artistic Gymnastics World Championships at M&S Bank Arena in Liverpool, England, Tuesday, November 1, 2022. (Photo by Thanassis Stavrakis/AP Photo)

Thailand's Lac Somruedee Pruepruk balances the ball during the sepak takraw women's match against Malaysia at the 31st Southeast Asian Games (SEA Games) in Hanoi on May 17, 2022. (Photo by Ye Aung Thu/AFP Photo)

A prototype Rollkers transportation device is displayed during a press event at the Mandalay Bay Convention Center for the 2015 International CES on January 4, 2015 in Las Vegas, Nevada. The product is not a skate; it balances for you and when you place it on the bottom of your shoe, it gives you the ability for faster transportation based on walking. The balance CES, the world's largest annual consumer technology trade show, runs from January 6-9 and is expected to feature 3,600 exhibitors showing off their latest products and services to about 150,000 attendees. (Photo by Ethan Miller/Getty Images)

An aerial view of rock salt collection pool made of tarpaulin, where rock salt is obtained by collecting the natural spring water in the mountains and evaporating the water, in Kozluk District of Batman, Turkiye on August 22, 2022. The production of rock salt, passed down from generation to generation, became the sole source of income for 45 households in the village of Derince, with a population of about 400 of Batman. (Photo by Omer Yasin Ergin/Anadolu Agency via Getty Images)

Two friends attempt to balance in the icy conditions in Newcastle, England on February 2, 2019. Boozy Brits across the UK took to the streets last night to ensure they got February off to a wet start after “Dry January”. (Photo by Craig Connor/North News and Pictures)

Young couples compete in Rock' n'Roll & Co, an all- Russian acrobatic rock' n'roll competition in Kazan, Russia on November 4, 2017. Acrobatic rock’n’roll is a discipline for couples combining energetic dancing with acrobatic moves. (Photo by Yegor Aleyev/TASS via Getty Images)

At the beginning of the 20th century, Edward S. Curtis set out to document what he saw as a disappearing race: the Native American. From 1907 to 1930, Curtis took more than 2,000 photos of 80 tribes stretching from the Great Plains to the Pacific Northwest and Alaska. He then published and sold these photos, along with narrative text, in 20 volumes of work known as “The North American Indian”. It is one of the most significant collections of its kind, “probably the most important photographic document of its age and its topic,” said Jeffrey Garrett, associate university librarian for Special Libraries at Northwestern University. (Photo by Edward S. Curtis)