Merit Prize Winner: “A Well Earned Rest in the Sahara”. This photo of Moussa Macher, our Tuareg guide, was taken at the summit of Tin-Merzouga, the largest dune (or erg) in the Tadrat region of the Sahara desert in southern Algeria. Moussa rested while waiting for us to finish our 45-minute struggle to the top. It only took ten minutes of rolling, running, and jumping to get back down. The Tadrat is part of the Tassili N'Ajjer National Park World Heritage area, famous for its red sand and engravings and rock paintings of cattle, elephants, giraffes, and rhinos that lived there when the climate was milder. Photo location: Summit of Tin-Merzouga, Tadrat, Tassili N'Ajjer National Park, Algeria. (Photo and caption by Evan Cole/National Geographic Photo Contest)

A woman struggles with an umbrella in the wind and rain while walking in Derby city centre, on December 23, 2013. (Photo by Rui Vieira/PA Wire)

Women jump into the water during a traditional New Year bath in the Adriatic sea in Portoroz, Slovenia on January 1, 2018. (Photo by Jure Makovec/AFP Photo)

American fashion model Simone Thompson, better known as Slick Woods walks at the Savage x Fenty – September 2018 – New York Fashion Week at Brooklyn Navy Yard on September 12, 2018 in Brooklyn, New York. (Photo by Presley Ann/Patrick McMullan via Getty Images)

A partial solar eclipse is seen in a break in the clouds during rush hour in downtown Wichita Kan., Thursday, October 23, 2014. A partial eclipse occurs when the moon covers a portion of the sun as seen from the Earth. (AP Photo/The Wichita Eagle, Travis Heying)

Everyone wants to get something for nothing - whether it's a lucky upgrade that means you can turn left when you get on a plane instead or heading off into the economy seats, or even getting a few extra features thrown in for free when you buy a new car.

As some of the sharpest businesses around, no-one understands this quite as well as casinos and that's why they all have a system that they call comps. It's short for "complimentary offers" and these are special treats specially designed to reward you for your loyalty to the casino in question. They're basically bonuses.

Dressed in traditional make-up and costume a woman participates in the celebration for the Day of the Dead or Día de los Muertos at the Hollywood Forever Cemetery in Los Angeles on Saturday, October 30, 2021. Day of the Dead, is a Mexican holiday where families welcome back the souls of their deceased relatives for a brief reunion that includes food, drink and celebration. (Photo by Richard Vogel/AP Photo)

Men give bananas to monkeys gathered on the side of the road as India remains under an unprecedented lockdown over the highly contagious coronavirus (COVID-19) on April 08, 2020 in New Delhi, India. Wild animals, including monkeys, are roaming human settlements in India as people are staying indoors due to the 21-day lockdown. (Photo by Yawar Nazir/Getty Images)