The colors of the rings are from the flags of the countries. Every country has at least one of the colors on their flag. The 5 rings represent the 5 particpating continents. At the time it was designed in the early 1900's North and South America were considered on continent. So you had America, Europe, Asia, Africa and Australia.
The Olympic rings represent the national flags that compete in the Olympic Games. It was originally designed in 1912 by Baron Pierre de Coubertin who introduced the meaning. You can go to http://en.wikipedia.org/wiki/Olympic_symbols for more reference.
9 months ago
Last edited at 11:45AM on 8/2/2012
It was originally designed so the 5 rings represented the 5 regions of the world where the athletes hailed from. The colors (and white background) was intended to represent the colors of all of the flags of the participants (at the time).