A man looks at a photograph by French photographer Robert Doisneau entitled “The Fate Line: Pablo Picasso at Vallauris, 1952” during the presentation of the photo-exhibition “Picasso, photographer's gaze”, on June 5, 2019 at the Picasso Museum in Barcelona. (Photo by Lluis Gene/AFP Photo)

Darth Vader balloon above Clifton Suspension Bridge during the hot air balloons mass ascent at sunrise on the first day of the Bristol International Balloon Fiesta on August 8, 2019 in Bristol, England. The Bristol International Balloon Fiesta is Europe's largest annual meeting of hot air balloons, attracting over 130 hot air balloons from across the globe. (Photo by Finnbarr Webster/Getty Images)

Pascal Martinot-Lagarde, of France, celebrates his bronze medal in the men's 110 meter hurdles final at the World Athletics Championships in Doha, Qatar, Wednesday, October 2, 2019. (Photo by Petr David Josek/AP Photo)

Two Herens cows lock horns during the qualification round of the annual “Battle of the Queens” cow fight finals in Aproz, in the western Alpine canton of Valais May 5, 2013. Each year when taken to the alpine pastures, the cows test their strength and fight for the herd's leadership. The competition continues until a new queen has forced all the other cows to retreat. (Photo by Valentin Flauraud/Reuters)

“Hiding In The Shadows”. This Baby Sandhill taking refuge under Moms wings while sitting on her second egg. I witnessed this baby being born earlier that day,and the next morning saw the other one hatch,what a sight to see. Photo location: Deland, Florida. (Photo and caption by Scott Helfrich/National Geographic Photo Contest)

This year's Republican National Convention and Democratic National Convention both saw passionate delegates in outrageous costumes – but that's where the similarities mostly end. Reuters photographer Jim Young gives a look at what it's like to be on the convention floor and talks to the delegates who make the conventions memorable. (Photo by Jim Young/Reuters)

In this third of seven sequential photos, Elian Gonzalez is held in a closet by Donato Dalrymple, one of the two men who rescued the boy from the ocean, right, as government officials search the home of Lazaro Gonzalez for the young boy, early morning, April 22, 2000, in Miami, Florida. Armed federal agents seized Elian Gonzalez from the home of his Miami relatives before dawn, firing tear gas into an angry crowd as they left the scene with the weeping 6-year-old boy. This photo won the Prize in 2001. (Photo by Alan Diaz/AP Photo)

Green building also known as green construction or sustainable building is the practice of creating structures and using processes that are environmentally responsible and resource-efficient.