Pneumonia is a disease of the lungs in which they become infected and inflamed. This can be due to a very large number of microorganisms like viruses and bacteria, but also due to environmental dangers such as chemical inhalation as well. It can be a very serious illness and is a leading cause of hospitalization. Many times, pneumonia only affects either one lung or the other, however sometimes double pneumonia (also known as bilateral pneumonia) may also occur. This particular type is often much more severe, and symptoms can be exacerbated greatly