Silverfish are nocturnal elongated and flattened insects typically 13-25 mm (0.5-1 in) long. Their abdomens taper at the end, giving them a fish-like appearance.
The newly hatched are whitish, but develop a grey hue and metallic shine as they get older.They have three long cerci at the tips of their abdomens one off the end of their body, one facing left, and one facing right. They also have two small compound eyes, despite other members of Thysanura being completely eyeless, such as the family .
Silverfish consume matter that contains polysaccharides such as starches and dextrin in adhesives. These include glue book bindings, plaster, some paints, paper, photos, sugar, coffee, hair, carpet, clothing, cotton, linen, silkm synthetic fibres and dead insects or even its own exuvia (moulted exoskeleton).
During famine, a silverfish may even attack leather wear and synthetic fabrics. Silverfish can live for a year or more without eating.