Why do most of dragonflies live near water?

'Odonata' is an order of carnivorous insects encompassing the dragonflies ('Anisoptera') and the damselflies ('Zygoptera'). The 'Odonata' form a clade, which has existed since the Permian.

Dragonflies are generally larger, and perch with their wings held out to the sides; damselflies have slender bodies, and hold their wings over the body at rest.

Odonates are aquatic or semi-aquatic as juveniles. Thus, adults are most often seen near bodies of water and are frequently described as aquatic insects. However, many species range far from water. They are carnivorous (or more specifically insectivorous) throughout their life, mostly feeding on smaller insects.

Eggs are laid in water or on vegetation near water or wet places, and hatch to produce pronymphs which live off the nutrients that were in the egg. They then develop into instars with approximately 9–14 molts that are (in most species) voracious predators on other aquatic organisms, including small fishes. The nymphs grow and molt, usually in dusk or dawn, into the flying teneral immature adults, whose color is not yet developed. These insects later transform into reproductive adults.