What is a moth?
Do I want to use the moth or insects?
A moth is an insect.
From thinking about it, I think that the moth is too ristricting.
A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. The differences between butterflies and moths are more than just taxonomy. Sometimes the names "Rhopalocera" (butterflies) and "Heterocera" (moths) are used to formalize the popular distinction. Many attempts have been made to subdivide the Lepidoptera into groups such as the Microlepidoptera and Macrolepidoptera, Frenatae and Jugatae, or Monotrysia and Ditrysia. Failure of these names to persist in modern classifications is because none of them represents a pair of "monophyletic groups". The reality is that butterflies are a small group that arose from within the "moths" and there is thus no way to group all of the remaining taxa in a monophyletic group, as it will always exclude that one descendant lineage.
There are thought to be 150,000 to 250,000 different species of moth, with thousands of species yet to be described. Most species of moth are nocturnal, but there are crepuscular and diurnal species.