An eight-year-old St Bernard with the longest canine tongue in the world, measuring 18.58cm (7.31in) in length, as recorded by the Guinness World Records: Amazing Animals, in South Dakota, USA. (Photo by Kevin Scott Ramos/GWR/PA Wire)

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.

“Grit and Glamour”, a retrospective of the late British photographer Elsbeth Juda, who fled Nazi occupation and came to England in 1933, is at the Jewish Museum, in London, until July 1, 2018. Here: Shelagh Wilson, Copacabana beach, Rio de Janeiro, 1951. (Photo by Elsbeth Juda Archive/Victoria and Albert Museum)

An Iraqi Kurdish Peshmerga female officer bites a snake while demonstrating skills during a graduation ceremony in the Kurdish town of Soran, about 100 kilometres northeast of the capital of Iraq's autonomous Kurdish region Arbil, on February 12, 2020. (Photo by Safin Hamed/AFP Photo)

A double rainbow is seen above a woman holding an umbrella and selling snacks along the road in Siaya county, Kenya on May 3, 2020. (Photo by Thomas Mukoya/Reuters)

A woman enjoys the sun at Plaka beach on the Aegean island of Naxos, Greece, Friday, May 14, 2021. Greece launched its tourism season Friday amid a competitive scramble across the Mediterranean to lure vacationers emerging from lockdowns. (Photo by Thanassis Stavrakis/AP Photo)

Dawn at Blyth beach huts in Northumberland, with the prospect of warm weather over the coming weekend on Friday, October 8, 2021. (Photo by Owen Humphreys/PA Images via Getty Images)

People in Kathmandu joke that the face mask has now become part of the national dress – an indispensable accessory in an effort to protect themselves from the dust. Nepal has the worst air quality in the world, according to the Environmental Performance Index. (Photo by Pete Pattisson/The Guardian)