Location, Location. Bronchitis is an inflammation/infection of the bronchial tubes (airways) whereas pneumonia is an infection/inflammation of the air sacs of the lungs (alveoli). Both can cause similar symptoms (fever, chest pain, cough, sputum production) but sound different when your health care provider listens to your lungs. Also pneumonia can typically be seen on chest xray and bronchitis cannot.
Location. Bronchitis is inflammation of the bronchial tree, the tubes leading to the lungs. It is often viral in origin. Pneumonia is an infection of lung tissue itself, usually bacterial, though can be viral or fungal. Sometimes bronchitis may progress to pneumonia. Treatment regimens depends on the organism causing the infection.
Location... Acute bronchitis is caused by an infection in the airways whereas pneumonia is the result of an infection in the lung parenchyma itself.