A software program that travels the Web (hence the name spider), locating and indexing websites for search engines.
Spiders are invertebrate animals in the phylum Arthropoda, which is a large group of animals with jointed legs and a hard outer skeleton. More specifically, they belong to the class know as Arachnida or more commonly referred to as Arachnids. Spider. A spider is a software program that travels the Web (hence the name spider), locating and indexing websites for search engines. All the major search engines, such as Google and Yahoo!, use spiders to build and update their indexes. Although most spiders live for at most two years, tarantulas and other mygalomorph spiders can live up to 25 years in captivity. While the venom of a few species is dangerous to humans, scientists are now researching the use of spider venom in medicine and as non-polluting pesticides. A program that automatically fetches Web pages. Spiders are used to feed pages to search engines. It's called a spider because it crawls over the Web. Another term for these programs is webcrawler. Because most Web pages contain links to other pages, a spider can start almost anywhere. Part of the Internet technologies glossary: A spider is a program that visits Web sites and reads their pages and other information in order to create entries for a search engine index. The major search engines on the Web all have such a program, which is also known as a crawler or a bot.. Spiders belong to the phylum Arthropoda, along with insects and crustaceans. The order of spiders, Araneae—together with scorpions, harvestmen, and the large order of mites and ticks—make up the class of Arachnida. Spiders differ from other arachnids in having the body divided into cephalothorax and abdomen. The spider for the AltaVista search engine and its Web site is called Scooter. Scooter adheres to the rules of politeness for Web spiders that are specified in the Standard for Robot Exclusion (SRE). It asks each server which files should be excluded from being indexed.
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what is a spider