Insects: Insects have six legs and three body segments. They include ants, bees, butterflies, cockroaches, and mosquitoes. Insects are the only arthropods (the animal division that includes insects and arachnids) that can fly. Some dragonflies can zoom up to 30 miles an hour (48 kph)!
Bugs: Bugs have specialized mouth parts and hardened front wings. They include cicadas, aphids, shield bugs, and bedbugs. All bugs are insects, but not all insects are bugs, which are defined by strawlike mouths made for sucking the sap from plants or (in the case of bedbugs) blood from living hosts.
Arachnids: Arachnids have eight legs and two body segments. They include spiders, ticks, mites, and scorpions. Spiders can spin webs of unbreakable silk to snare prey. They instill greater fear in humans than any other animal, despite the fact that spiders are relatively harmless compared with insects.
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