Difference between Spider and Insect (Spider vs Insect)

Spider (Aranea): it is a cosmopolitan arachnid. It is carnivorous and feeds o insects,  sow walking in locomotion and respires with the help of book lungs. Sexes are unisexual and show dimorphism. Fertilization is internal and female is oviparous. Eggs are laid in silken oothecae, Development is direct.

Body is divisible in two parts: cephalothorax and abdomen. Cephalothorax bears one pair of pedipalpi, one hair of chelicerae and 4 pairs of walking legs. The abdomen bears spinnerets to spin the silk thread to make web.

Insects: It is the largest class of animals and includes more than 750000 species. Body is divided into three parts: head, thorax and abdomen. Thorax always has  three pairs  of jointed legs so called hexapoda. Thorax generally has one or two pairs of wings. Habitat is variable. Respiration is by trachea. Excretion is by malpighian tubules. These have one pair of antennae.

Example of insects: Cockroach(Periplaneta), Silver fish (Lepisma), termite- White ant (Microtreme), Honey bee (Apis), Headlouse(Pediculus), Rat flea (Xenopsylla), Silk moth(Bombayx mori), mosquito(Culex/ Anopheles)

Spider Vs Insect

Spider	Insect
Body is divided into two parts: Cephalothorax and abdomen.	Body is divided into two parts: head, thorax and abdomen.
Mouth parts: Have chelicerae and pedipalpi	Mouth parts: Have labrum, labium maxillae and mandibles.
Wings absent	Wings generally present
Four pairs of legs	Three pairs of legs
Antennae absent	One pair of antennae present
Spinnerets present on abdomen and used to form spider web	Spinnerets absent