Spiders are predatory invertebrate animals with two body segments, eight legs, no chewing mouth parts and no wings.

They are classified in the order Araneae, one of several orders within the larger class of arachnids, a group which also contains scorpions, whip scorpions, mites, ticks, and opiliones (harvestmen).

The study of spiders is known as arachnology.

All spiders produce silk, a thin, strong protein strand extruded by the spider from spinnerets most commonly found on the end of the abdomen.

Many species use it to trap insects in webs, although there are many species that hunt freely.

Silk can be used to aid in climbing, form smooth walls for burrows, build egg sacs, wrap prey, and temporarily hold sperm, among other applications.

For more information about the topic Spider, read the full article at Wikipedia.org, or see the following related articles:

Yellow sac spider — The Yellow sac spider (Cheiracanthium inclusum) is not a true sac spider but a long-legged sac spider. It is one of a handful of spiders in North ...  > read more

Opiliones — The Phalangids (legacy name) or Opiliones (better known as "harvestmen") are eight-legged invertebrate animals belonging to the order Opiliones in ...  > read more

Hobo spider — The Hobo Spider (Tegenaria agrestis) is a member of the genus of spiders known colloquially as funnel web spiders. The spider's venom is strong ...  > read more

Brown recluse spider — The brown recluse spider is a venomous spider, Loxosceles reclusa. It is usually between 1/4 and 3/4 inch (6.4-19.1mm) but may grow larger. It is ...  > read more

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