Asthma affects millions of people around the world every day. Asthma can keep you from taking part in your favorite sport or even make taking a single breath difficult. Even if you don't have asthma, you probably have family or friends who do. Asthma can even be deadly in some cases, making it much more than just an annoying cough or a bit of trouble breathing. You may hear about asthma on TV and read about it online. But many people-kids and adults-don't understand much about asthma. What does asthma do to your body? Why do some people have asthma while others don't? What is life like for the people around the world who have asthma or live with someone who does? How can people live normal lives while taking care of their asthma? You'll find answers to all of these questions and more