The answer to 'what is bed bug' is bed bugs are small, flat insects that feed on human blood. They are about the size of an apple seed and can be hard to see. Bed bugs typically hide in cracks and crevices around the bed, and come out at night to feed on sleeping people. Bed bug bites can cause itchy red welts on the skin, but they do not spread disease.
Bed bugs are a common household pest that can be difficult to get rid of. They can spread quickly by hitchhiking on clothing, furniture, and other items. Homeowners should be vigilant for signs of bed bugs and take prompt action to eliminate an infestation.