Giving out with a yell, Elke Sommer is tossed on the trampoline as she trains for her movie role as an athlete, on the playing field of the University of California at Los Angeles, June 8, 1967. (Photo by AP Photo)

The 20-year-old American fashion model Kaia Jordan Gerber – who is the daughter of supermodel Cindy Crawford, 55, and businessman Rande Gerber, 59 – poses braless as she stuns in an edgy shoot in January 2022. (Photo by Ports 1961’s Spring/Summer Campaign)

Belgium's Lisa Ingenito competes in the Mixed Artistic Swimming duet technical final on August 15, 2022 during the LEN European Aquatics Championships in Rome. (Photo by Filippo Monteforte/AFP Photo)

Dawlish Carnival 50th anniversary pram race featuring the famous Dawlish Black Swan in England on August 15, 2023. (Photo by nidpor/StockimoNews/Alamy Live News)

Amundsen-Scott South Pole Station experiences months of darkness. The sun dips below the horizon on March 21, after which follows several weeks of twilight before complete darkness results. Photo taken on June 25, 2009. (National Science Foundation/Jeremy Johnson)

American singer Tinashe Jorgensen Kachingwe, known mononymously as Tinashe attends the 2021 MTV Video Music Awards at Barclays Center on September 12, 2021 in the Brooklyn borough of New York City. (Photo by Andrew Kelly/Reuters)

Australia's Nina Kennedy competes in the women's pole vault final at a Diamond League event in Florence, Italy on June 2, 2023. (Photo by Remo Casilli/Reuters)

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.