Wasps like this ichneumon wasp have two pairs of wings. Most insect groups are named after their types of wings. The family of the wasps is called Hymenoptera (membrane winged). Each pair of wings is attached to the other by hooks to form one membrane.

Compare these with the wings of a fruit fly.

 
Part of the Collection of the Insect Portrait Gallery of the Micropolitan Museum © Wim van Egmond