Why is soccer the worlds most popular sport?

Kicking games have always been around it seems. Many different countries claim to have inented it, and I believe that similar games sprang up in different areas of the world without any contact between those countries. All that aside, perhaps the biggest reason soccer is so popular is because it requires nothing but a ball and even the ball doesn't have to meet special standards as long as it suits the purpose. I have seen boys in Africa take dozens of plastic bags and tie them together making a ball of sorts and with some rocks (or anything else) as post markers, the game is on! Another reason is that a lot of people can play at once.