Abby Dow (L) of England scores a try during the Women's Rugby World Cup Semi Final match between Canada and England at Eden Park in Auckland, New Zealand, 05 November 2022. (Photo by Aaron Gillions/EPA/EFE)

People participate during the Carnival parades in Port-au-Prince, Haiti, 21 February 2023. Haiti tries to forget the crisis and violence for a few days and has taken to the streets to dance to the rhythm of carnival, a party that comes to an end on 21 February in Port-au-Prince. (Photo by Johnson Sabin/EPA)

A fox cub with some bluebells in some woodland at Wye Valley near Gloucester, United Kingdom on April 29, 2023. (Photo by Thomas Winstone/Picture Exclusive)

A member of the Gumatj clan performs a ceremonial welcome during the Garma Festival at the Gulkula ceremonial in the Gove Peninsula of the Northern Territory, Australia 03 August 2024. The Garma Festival is Australia’s largest Indigenous gathering, a 4-day celebration of Yolngu life and culture held in remote northeast Arnhem Land. (Photo by Mick Tsikas/EPA)

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.

Russia's Maria Stavitskaia performs during the ladies short program at the Rostelecom Cup ISU Grand Prix of Figure Skating in Moscow November 14, 2014. (Photo by Grigory Dukor/Reuters)

The competition, which is run by the Royal Observatory Greenwich in association with BBC Sky at Night Magazine, is now in its sixth year and has received over 2,500 entries. Photo: Centre of the Heart Nebula by Ivan Eder (Hungary). Situated 7500 light years away in the “W”-shaped constellation of Cassiopeia, the Heart Nebula is a vast region of glowing gas, energized by a cluster of young stars at its centre. The image depicts the central region, where dust clouds are being eroded and moulded into rugged shapes by the searing cosmic radiation. (Photo by Ivan Eder)