the biggest hamburger restaurant chain in the world is McDonald’s. it started in 1955 with just one restaurant ,but now has more than 20,000 of them worldwide. There are more than 12,000 McDonald’s restaurants in the US alone. You can find them in 100 countries on six continents. There isn't McDonald's in antarctica, but i don't suppose they eat hamburgers at the south pole. When you eat at a McDonald's restaurant you are joining the 35 million people who eat and drink at McDonald's every day ,and the more than one million people who work there.Mcdonald's has sold 100 billion hamburgers since it opened, and it sells more than 6.8 million pounds of French Fries every day.