Insect scientists (Entomologists) categorize groups of living entities as how they are related through the Theory of Evolution. In an order, there are classes, orders, suborders, families and genera, which constitute the living things that procreate with one another. More than 1 million of the categorized 2 million species are arthropods (insects/spiders).
INSECTS: (Class Insecta):
Order: Blattodea ("insect avoiding light")
Species: 3,700
Example: Cockroach
Order: Coleoptera ("hard wings")
Species: 400,000
Example: Ladybug
Order: Collembola ("sticky peg")
Species: 6,000
Example: Springtail
Order: Dermaptera ("leathery wings")
Species: 1,800
Example: Earwigs
Order: Diptera ("two wings")
Species: 120,000
Example: Mosquito
Order: Embioptera ("")
Species: NA
Example: Webspinners
Order: Ephemeroptera ("living for a day")
Species: 2,100
Example: Mayflies
Order: Grylloblattodea ("")
Species: NA
Example: Ice Insect
Order: Hemiptera ("half wings")
Species: 82,000
Example: Cicada
Order: Homoptera ("")
Species: NA
Example: Leafhopper
Order: Hymenoptera ("membrane wings")
Species: 130,000
Example: Ant / Bee
Order: Isoptera ("equal wings")
Species: 2,300
Example: Termite
Order: Lepidoptera ("scaly wings")
Species: 150,000
Example: Butterfly
Order: Mallophaga ("")
Species: NA
Example: Chewing Louse
Order: Mantodea ("like a prophet")
Species: 1,800
Example: Praying Mantis
Order: Mecoptera ("long wings")
Species: 400
Example: Scorpion Fly
Order: Megaloptera ("")
Species: NA
Example: Alderfly / Dobsonfly
Order: Microcoryphia ("")
Species: NA
Example: Bristletail
Order: Neuroptera ("net-veined wings")
Species: 5,000
Example: Lacewings
Order: Odonata ("toothed flies")
Species: 5,500
Example: Dragonfly
Order: Oleoptera ("")
Species: NA
Example: Beetle
Order: Orthoptera ("straight wings")
Species: 20,500
Example: Cricket
Order: Phasmatodea ("like a ghost")
Species: 2,500
Example: Walking Stick
Order: Phthiraptera ("louse wings")
Species: 3,000
Example: Lice
Order: Piecoptera ("wickerwork wings")
Species: 2,000
Example: Stonefly
Order: Protura ("")
Species: NA
Example: Proturan
Order: Psocoptera ("milled wings")
Species: 3,200
Example: Woodlice
Order: Raphidoptera ("")
Species: NA
Example: Snakefly
Order: Siphonaptera ("tube without wings")
Species: 2,400
Example: Flea
Order: Strepsiptera ("")
Species: NA
Example: Parasite
Order: Thysanoptera ("fringed wings")
Species: 5,000
Example: Thrip
Order: Thysanura ("bristle tails")
Species: 370
Example: Silverfish
Order: Trichoptera ("hairy wings")
Species: 10,000
Example: Caddisfly
Order: Zoraptera ("")
Species: NA
Example: Zorapteran
SPIDERS: (Class Arachnida; Order Araneae):
Order: Labidognatha
Families: 90
Species: 32,000
Example: House Spider
Order: Orthognatha
Families: 15
Species: 3,000
Example: Tarantula
Order: Mesothelae
Families: 1
Species: 24
Example: Segmented Spider