The olympic rings were made by Baron Pierre (founder of the modern Olympic Movement) in 1914 after he saw a similar design on an artefact from ancient greece. The five rings represent the five major regions of the world Africa, the Americas, Asia, Europe, and Oceania. Every national flag in the world includes at least one of the five colors, which are (from left to right) blue, yellow, black, green, and red.
The white background on the olympic flag represents peace and truth.
