Bed bugs have been known as human parasites for thousands of years. Bed bugs adult is oval, broadly flattened blood sucking insect, and possess mall wind pads, or we can say wingless. Bed bugs are usually brown in color before feeding, and become red in color after full blood meal which takes 3-5 minutes to get full blood meal. Under cool conditions, bed bugs have been able to survive up to a year without a meal. They are more active during night when the host is asleep. Bed Bugs found in cracks and crevices, including mattress seams, sheets, furniture, behind baseboards, electrical outlet plates and picture frames. Often found in hotels.

American cockroach adults grow to an average length of around 4 cm (1.6 in) and about 7 mm (0.28 in) tall. They are reddish brown and have a yellowish margin on the body region behind the head. Immature cockroaches resemble adults except they are wingless. The cockroach is divided in three sections; the body is flattened and broadly oval, with a shield-like pronotum covering its head. A pronotum is a plate-like structure that covers all or part of the dorsal surface of the thorax of certain insects. They also have chewing mouth parts, long, segmented antennae, and leathery fore wings with delicate hind wings. The third section of the cockroach is the abdomen.

German cockroach (Blattella germanica) is a small species of cockroach, typically about 1.1 to 1.6 cm (0.43 to 0.63 in) long. In colour it varies from tan to almost black and it has two dark, roughly parallel, streaks on the pronotum running anteroposteriorly from behind the head to the base of the wings. German cockroaches are omnivorous scavengers. They are attracted particularly to meats, starches, sugars and fatty foods. Where there is a shortage of foodstuffs, they may eat household items such as soap, glue and toothpaste. In famine conditions they turn cannibalistic, chewing at each other's wings and legs.