Millipedes can vary from ½ to 6 ½ inches in length and are brown. They have 2-4 pairs of legs per segment of body. Millipedes normally live in and feed on rotting leaves, rotting wood, and other kinds of moist, decaying plant matter. Generally, their role is a beneficial one in helping to break down dead plant matter. They prefer moist areas, so if they do make it inside they will not live very long due to the dry conditions and lack of food.
Adult centipedes are usually brownish and more than 1 inch long. They have one pair of legs per body segment. When provoked, a few large kinds of centipedes can inflict a painful bite that may cause localized swelling, discoloration, and numbness. They are usually found in damp, dark places such as under stones, leaf mulch, or logs. Indoors, centipedes may occur in damp areas of basements, closets, or bathrooms, or anywhere in the home where insects occur. During the day they hide in dark cracks and crevices, coming out at night to search for insects to eat.