A person who collects and studies butterflies is called a lepidopterist. Lepidopterology (also lepidoptery) is a branch of zoology dealing with both butterflies and moths.
Amateur butterfly collectors capture butterflies, which are then euthanized in jars with chloroform and pinned to a display board that is typically made of foam or cork. The wings of the insects are extended for best viewing of shapes and colors and carefully fastened to the board with long, thin pins, much like needles. The butterflies are then labeled, often with both their scientific names and common names, and the board is placed in a display cabinet to preserve the insects.
Scientists in the field of lepidopterology study euthanized insects using both hand lenses and microscopes that allow them to examine the specimens in detail. The scientists may also perform chemical composition and DNA exams on specimens. Other lepidopterists study live insects by creating butterfly gardens and rearing cages to use as observation stations.