Dragonflies are carnivorous flying insects that rule the air in the insect world. Like most groups of insects, dragonflies have a large variety of species, sometimes nearly indistinguishable unless you are an expert, and even then you might need to examine a live specimen, not just look at a photograph that might only show part of the animal from one angle. I am not going to state the exact species only a guess here, since I am even more uncertain than usual.
A dragonfly looks kind of like a helicopter but its body is a lot more nimble and maneuverable.
Dragonflies are fearsome predators throughout their entire lifetime, the larvae eat whatever they can overpower under water. Then one day they climb out of the water, molt and become helicopter-like adults that can catch other insects in the air with the greatest of ease.
Dragonfly larvae eat mosquito larvae, and adult dragonflies love to dine on mosquitoes, catching them in flight. Just remember that before you try to kill a dragonfly for your bug collection!
Most adult dragonflies are quite beautiful.
Coloration can be almost anything, the brightest metallic reds, yellows, blues and greens are quite common, some species are even metallic looking black.
These specimens were photographed at various occasions when I took quick walks in Milliken Park and they were just sitting right in front of me. Unfortunately I seem to be unable to determine unequivocally what species each one is, hence the somewhat sloppy description. I apologize, but I always find insect identification tedious.