Most rice cookers have an aluminum or stainless steel inner bowl, which sits atop a heating unit.  The bowl is filled with rice and water, and the rice cooker automatically heats the rice for the correct amount of time at the proper temperature ensuring a tasty result every time. 

Some rice cookers have a timer that allows the cook to specify when the rice is to finish cooking. This allows you to concentrate cooking the rest of the meal, and be sure that your side dish will be ready at the perfect time.

During the cooking process, all of the water is absorbed into the rice.  This results in a healthier meal, since none of the rice’s nutrients are lost when the water is drained.

Once the rice is finished, the cooker either turns itself off or it keeps the contents warm for up to 24 hours.  The warming feature helps to reduce the chance of bacteria settling on the finished dish, eliminating the chance of food poisoning.

Many rice cookers have the proper amount of rice marked on the inner bowl.  A nice additional feature in some cookers is having additional marks for different types of rice, which have different cooking times.  For example, brown rice and Japanese rice require different proportions of rice to water and cooking times, than plain white rice.