A tattoo artist applying ink on a girl' s arm during the 2017 Moscow Tattoo Festival at Moscow' s Amber Plaza Shopping Center in Moscow, Russia on April 1, 2017. Tattoo artists from all over the world take part in the event. The festival' s program includes a tattoo contest, body taping art marathon, masterclasses, round table discussions and conferences. (Photo by Valery Sharifulin/TASS)

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.

A woman controls a ball on Ipanema beach in Rio de Janeiro, Brazil, April 14, 2016. As hundreds of thousands of tourists begin descending on Rio de Janeiro for the Olympics that start August 5, the headlines have focused on the street violence, the Zika virus, the water pollution and the rush to finish venues and transport. But Rio, known by Brazilians as the “Marvelous City”, glistens despite it all. The beach is a way of life here. (Photo by Nacho Doce/Reuters)

Christ the Redeemer is seen from the Vista Chinesa (Chinese View) during sunrise in Rio de Janeiro, Brazil, May 4, 2016. Rio de Janeiro is a marvel and a mess all at once. When it hosts the first ever Olympics in South America, starting Aug. 5, visitors will see a city whose stunning topography – stark, verdant mountains loom over packed and playful beaches – competes only with the drama of daily life here. (Photo by Ricardo Moraes/Reuters)

Some creations from the new “Funny Food Made Easy” book by Bill and Claire Wurtzel. “Inspiring kids to eat healthy foods with creative works of plate art and easy-to-follow instructions and illustrations. Through finished plate art, detailed step-by-step illustrations, recipes, and tips, Funny Food Made Easy provides all you and your kids need to make, eat, and enjoy healthy breakfasts, lunches, and snacks” – roughly speaking so. Here: Egg, cucumber, olive. (Photo by Bill and Claire Wurtzel/Welcome Books)

Life as tenant farmers in Kasungu, northern Malawi, can be a struggle for families trapped in poverty, who feel forced to rely on their children’s help, impacting schooling. Here: A tobacco field at a farm in Kasungu region, Malawi. Tobacco is the country’s most important export crop, with tobacco leaf from Malawi filling cigarettes found all over the world. Here: Tiyamike Phiri hopes to become a nurse because she wants to travel the country and help others. (Photo by David Levene/The Guardian)

These sand-swept images show the ghostly remains of what was once a mineral-rich mining community. In its heyday, the town of Kolmanskop, Namibia, was home to about 700 families. Now all that remains are empty homes filled with sand, while cast-off items such as bathtubs are scattered about the surrounding area. Over time, the sand of the stunning dunes that encircle the town of Kolmanskop has been blown towards the abandoned residences, coating everything from streets to the interiors of houses and workshops. Here: Kolmankop, an abandoned mining town in Namibia. (Photo by David Ogden/Caters News)