The dragonfly is of the order odonata, meaning the "toothed one". They primarily eat small flying insects, particularly mosquitos. They are of often referred to as "mosquito hawks", and are very beneficial. Dragonflies are harmless to humans, and do not sting or bite, however if they land on you they may try to nibble, but their mouths are to small to cause any harm.
Photographed this dragonfly at the pond in the the RV park. Numerous in the spring and summer, and during the mating season in late summer. early fall. Some species of dragonflies will fly right up to you, look you over as if curious as to what you are.