Week 4

The Olympic rings were designed by Pierre de Coubertin, the founder of the modern Olympic Games. The symbol first appeared in the Paris magazine "Le Bon Marche" in 1913 and it was approved at the Olympic Congress in 1914.
De Coubertin originally intended the symbol to celebrate the 20th anniversary of the modern Olympics in 1916, but the Games were cancelled because of World War I. At the 1920 Olympics in Antwerp, Belgium, the Olympic flag was hoisted for the first time and the rings became the official Olympic symbol. The flag has the five rings on a white background, with no border.
The rings were meant to represent the five previous modern Olympic games. However, they soon came to represent the five continents.
The top three rings are blue, black, and red; the bottom two are yellow and green. The colors were chosen because every country in the world uses at least one of them (including the white background) on its official flag.
It's often said each ring represents a specific continent, but the IOC says that isn't so. For the record, though, here are the continents that the rings are said to represent:
Blue - Europe
Black - Africa
Red - America
Yellow - Asia
Green - Oceania
The Olympic flag is hoisted during the opening ceremony and lowered at the closing ceremony to signify the end of the Games.
The rings were first shown on Olympic medals for the 1928 Winter Olympics, and they've appeared on all Winter Olympic medals since then. However, they didn't show up on Summer Olympic medals until the 1956 equestrian competition, which was held in Sweden because of Austtralia's embargo against bringing horses into the country. Since 1976, they've also appeared on the medals at all Summer Olympics.