How do the ancient and modern olympics different

1.The ancient Olympic games only allowed people of Greek descent to participate. The Salt Lake City Olympics feature 2600 athletes from 77 countries. Only a few hundred athletes participated in the ancient games. 
2.Only men were allowed to compete in the ancient Greek games. Athletic training in ancient Greece was part of every free male citizen's education. The first women to compete in the Olympics were Marie Ohnier and Mme. Brohy. They participated in croquet games in the 1900 Olympics.