Ladybugs (Coccinellids) are generally considered useful insects as many species feed on aphids or scale insects,which are pests in gardens,agricultural fields,orchards,and similar places.The Mall of America,for instance,releases thousands of ladybugs into its indoor park as a natural means of pest control for its gardens.[3] Some people consider seeing them or having them land on one's body to be a sign of good luck to come,and that killing them presages bad luck.A few species are pests in North America and Europe.
Cockroaches (or simply "roaches") are insects of the order Blattaria.This name derives from the Latin word for "cockroach",Barata.There are about 4,000 species of cockroach,of which 30 species are associated with human habitations and about four species are well known as pests.