The Spanish photographer Xavi Bou digitally combines sequential pictures of birds to create a single image, or chronophotograph, that reveals the shapes of their flight paths against Catalonian skies. His work shows the variety and beauty to be found in the daily activities of the local birds, including spiralling storks, swooping starlings and giddy swifts. Here: European herring gulls at Llobregat Delta. (Photo by Xavi Bou/Rex Features/Shutterstock)

An attendee takes a selfie at KCON USA, billed as the world's largest Korean culture convention and music festival, in Los Angeles, California on August 11, 2018. K-pop acts sing or rap in Korean, often with snippets of English. On the Web, where K-pop fandom thrives, many music videos include subtitles. (Photo by Mike Blake/Reuters)

Festival goers splash through a muddy puddle at Worthy Farm in Somerset, on the third day of the Glastonbury music festival June 27, 2014. (Photo by Cathal McNaughton/Reuters)

Gothic enthusiast poses during the annual Wave-Gotik-Treffen music festival on May 26, 2012 in Leipzig, Germany. The event began in the 1990s and has since grown into one of the biggest gatherings of Goth scene followers in Europe with around 20,000 participants. (Photo by Adam Berry)

Festival goers having fun at the Balaton Sound music festival in Zamardi next to the Lake of Balaton, 110 km (68 miles) west of Budapest, July 6, 2017. (Photo by Zsolt Furesz)

Girls play in the water during the Balaton Sound music festival held on the shore of lake Balaton in Zamardi, west Hungary, on July 9, 2017. (Photo by Sandor Csudai/Rockstar Photographers)

Festival goers kiss in the “Silent Disco” at the “Music in the Park” stage during the 50th Montreux Jazz Festival, in Montreux, Switzerland, July 9, 2016. (Photo by Anthony Anex/EPA)

Kat Graham attends the 2015 MTV Video Music Awards at Microsoft Theater on August 30, 2015 in Los Angeles, California. (Photo by Mike Windle/Getty Images for MTV)