Cockroaches are one of the oldest living insects, with fossils dating back 350 million years. There are over 4,000 species worldwide, with about 50-60 species found in the United States. The three most common species that live in homes are the German, Oriental, and American cockroaches. Cockroaches can survive for weeks without food and are hardy insects that reproduce quickly. Proper sanitation and pest control are needed to prevent cockroach infestations.