Wikipedia
The five Olympic rings represent the five continents involved in the Olympics and were designed in 1912, adopted in June 1914 and debuted at the 1920 Antwerp Olympics.
The current view of the International Olympic Committee (IOC) is that the symbol "reinforces the idea" that the Olympic Movement is international and welcomes all countries of the world to join. As can be read in the Olympic Charter, the Olympic symbol represents the union of the five continents and the meeting of athletes from throughout the world at the Olympic Games. However, no continent is represented by any specific ring.