A Somali police officer arrests a suspected rebel member of the al Qaeda-affiliated al Shabaab among beach goers in Mogadishu. Al Shabaab claimed responsibility for today's pre-dawn attack on a Kenyan university campus near the Somali border. The following gallery examines who is al Shabaab. Here: Somali police officer (R) arrests a suspected rebel member (L) of the Al Qaeda-affiliated al Shabaab among beach goers at the Lido beach north of Somalia's capital Mogadishu March 23, 2012. (Photo by Feisal Omar/Reuters)

Russia's Ekaterina Birlova casts a shadow on the sand as she serves to Poland during a women's beach volleyball match at the 2016 Summer Olympics in Rio de Janeiro, Brazil, Tuesday, August 9, 2016. (Photo by Marcio Jose Sanchez/AP Photo)

The Tianzi Hotel with the shape of Chinese deities Fu, Lu and Shou is pictured on November 20, 2017 in Langfang, Hebei Province of China. The 41.6-meter-tall Tianzi Hotel has an exterior of Chinese Sanxing, whose names are Fu, Lu and Shou with the qualities of prosperity, status and longevity in traditional Chinese culture, in Langfang city. (Photo by VCG/VCG via Getty Images)

A woman looks at artwork called “Alphabetti Spaghetti” by British sculptor Alex Chinneck, one of a series of “knotted” postboxes, installed as part of a public art trail for Kensington & Chelsea Art Week on October 3, 2020. (Photo by Victoria Jones/PA Images via Getty Images)

A model parades an outfit by Australian label Micky In The Van at Melbourne Fashion Week in Melbourne on November 18, 2021. As Australian labels were paraded on the runway at Melbourne Fashion Week, protests took place outside by female warehouse workers claiming they are earning up to $10 less an hour than male counterparts. (Photo by William West/AFP Photo)

The World Enduro Super Series roared back into life this weekend with Mario Roman coming out on top at the Toyota Porto Extreme XL Lagares on May 12 to stake an early claim for the title of Ultimate Enduro Champion 2019. The Spaniard beat the 300 competitors, including 50 pros, who entered Sunday's Hard Enduro feature race in the baking Portuguese heat. Here: Graham Jarvis and Billy Bolt race at Toyota Porto Extreme XL Lagares, Portugal on May 12, 2019. (Photo by Future7Media/Red Bull Content Pool via AP Images)

Model Elise Daniels dons a Balenciaga suit while surrounded by street performers in Paris, France in 1948. (Photo by Richard Avedon/Victoria and Albert Museum London/The Guardian)

Iranian bodybuilder Sharareh Nobahari, 30, assists her fitness trainees at a gym in Tehran, Iran on September 20, 2019. (Photo by Nazanin Tabatabaee/Reuters)