If you need more creative control, the shutter and aperture priority features can be quite useful. Unless you're using high-speed film and a tripod, most cameras are useless indoors without a flash. Fortunately, most cameras, even the basic ones, feature a flash that fires automatically in low-light situations. Most midrange to high-end cameras let you select different modes for the automatic flash. Red-eye reduction helps eliminate the tendency for people to have demonic red eyes in photographs.
Red eye is a result of light bouncing back at the camera from subjects' retinas.
Flash off mode prevents the flash from firing in inappropriate situations, such as in museums or at the theater, where flash photography is forbidden. Flash fill-in mode enables you to fire the flash in odd light situations, when your background is bright but your subject is in shadow, or when you photograph a person in front of a sunset. Some advanced cameras offer flash synch mode as well, which fires a flash and then leaves the shutter open for a relatively long time period. Flash synch works well for taking pictures of people in front of night scenes. All but the most basic models offer automatic film transport between shots.