The galactic core of the Milky Way glows brightly in the clear night sky above St Catherine?s Chapel at Abbotsbury in Dorset, UK on August 2, 2024. (Photo by Graham Hunt/Alamy Live News)

(L-R) Singers Kelly Rowland, Beyonce and Michelle Williams perform during the Pepsi Super Bowl XLVII Halftime Show at the Mercedes-Benz Superdome on February 3, 2013 in New Orleans, Louisiana. (Photo by Ezra Shaw/Getty Images)

Meet the star students of orangutan school – the unique rehab centre where orphaned apes are taught how to climb trees and survive in the wild without their mum and dad. (Photo by Caters News)

James Brady and a police officer are seen lying on the ground after being shot while the suspect John Hinckley Jr. is apprehended,at right, moments after the attempted assassination of President Ronald Reagan, Washington, DC, March 30, 1981. (Photo by Dirck Halstead/Getty Images)

Kacey Musgraves and Gigi Hadid attend the 53nd annual CMA Awards at Bridgestone Arena on November 13, 2019 in Nashville, Tennessee. (Photo by Charles Pulliam/Reuters)

Chechen Interior Minister Ruslan Alkhanov greets participants of the military parade to mark the Victory Day in Grozny, Russia, May 9, 2015. Russia marks the 70th anniversary of the end of World War Two in Europe on Saturday with a military parade, showcasing new military hardware at a time when relations with the West have hit lows not seen since the Cold War. (Photo by Reuters/Host Photo Agency/RIA Novosti)

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 reveler dances during the Carmelitas street party in Rio de Janeiro, Brazil, Friday, March 1, 2019. Much of the appeal of Rio street parties is the variety of themes and that people can dress up in costumes or not. (Photo by Leo Correa/AP Photo)