Ultrasound of the lung can be used to assess neonatal respiratory conditions and is an emerging bedside technique. All signs of lung ultrasound emerge from the pleural line, and are based mainly on artifacts (traditionally considered undesirable). These artifacts arise from air-fluid interfaces within the thorax. Lung ultrasound findings are dynamic, since the lungs are always moving. Several signs such as the bat sign, the seashore sign, the quad sign, and ‘lung rockets’ are described.