For every cockroach you see, there can easily be 200 more hiding behind your wall. The most troublesome type is the German Cockroach
Other types include:
The largest house-infesting species, about one and one-half inches long reddish-brown wings light markings on thorax very aggressive prefer warm, damp areas more likely to be seen in daytime and outdoors than other species scavengers that will eat almost anything commonly found in food preparation areas can live up to 15 months
Brown Banded Cockroach:
About five-eighths inch long wings have two brownish-yellow bands nocturnal can fly may be found throughout any structure, but prefer dry, warm areas, high locations, and inside furniture scavengers that will eat almost anything adults live up to 10 months
About five-eighths inch long light to medium brown nocturnal primarily infest areas close to food, moisture and warmth most common cockroach found in and around apartments, homes, supermarkets and restaurants scavengers that will eat almost anything adults can live up to one year extremely heavy infestations are not uncommon widest distribution of all cockroaches in U.S.
Dark brown about one inch long common outdoors often enter buildings through sewer pipes tend to live near the ground and in warm damp areas eat anything, but found often feeding on garbage, sewage, and decaying organic matter seem to prefer starches if available adults can live up to 180 days more sluggish than other species give off distinctive unpleasant odor
Smokey Brown Cockroach:
Dark brown, up to one and one-half inches long prefers to live outdoors populations are relatively immobile compared to other species scavengers that will eat almost anything normally feed on plant material adults can live up to 200 days particularly numerous in southeastern U.S. fly towards lights at night.