Do you recognise this flag? Here's a clue - you only see it once every four years in a different country each time. This summer it's coming home to Greece!
I know - it's the Olympic Flag, and the five rings are symbols for the five parts of the world that were joined together by the Olympics - Europe, Australasia, Africa, Asia and the Americas. But what do you mean, "it's coming home?"
The Olympics is "coming home" because the Games began in Greece. Click on the flag to find out how the Olympics started, and what they were like all those years ago.
Today, millions of people from all over the world watch the Olympics. Each host country tries to outdo the last in having the most spectacular opening and closing ceremonies. Here, you can see a party in Beijing, China to celebrate the country's success in hosting the next Olympics in 2008.
At the Olympics in Sydney, Australia in 2000 there were competitors from 199 countries. They competed in 28 different sports in 33 separate venues. Can you unscramble the letters to find the names of some of these sports?
The table shows the medals won by ten countries at the last Olympics. Click here to see if you can work out the answers to some questions on this medals table. After you have had a go, click here for the answers.
Poorer countries can't afford to send many athletes to the Olympics. What's more, poorer countries do not have the training facilities, equipment and coaching enjoyed by other competitors. And sponsors from big companies can help cover some of the costs of training and travel in richer countries.
With these extra hurdles to jump, poorer countries find it easier to compete in some sports than others. Imagine you are running the Olympic team in a poorer country - put these sports in order from the easiest (1st) to the most difficult (6th) for you to have a good chance of winning an Olympic medal.
In some ways, this means that some countries have a head start when they take part in the Olympics ... do you think this is fair?
This does not stop some countries from winning medals. Some of the world's best runners come from Ethiopia, one of the world's poorest countries. Haile Gebreselassie, on the left of the picture, won a gold medal. He used to run ten kilometres to school every morning and then back again! Today, he still runs with a crooked left arm after years of running to school carrying his books!
Greece has been planning for years for the Olympics 2004. Imagine you are starting from scratch to prepare for the Olympics. Where would you start? Click here to have a go.
London is one of the cities that would like to hold the Olympics in 2012. But is it a good idea? Would you be 'for' or 'against' holding the Games in London?
Write a letter to the organisers of the London Olympic Committee, either as a keen sports fan in support of the bid, or as an angry resident who thinks it's a terrible idea.
Make your letter as persuasive as possible! Click here if you need some help with some arguments to include in your letter.