Spiders

(1) (Spider) A gaming platform from AMD. See Phenom.

(2) Also known as a "crawler," "robot" (bot) and "intelligent agent," a spider is a program that searches for information on the Web. Spiders are widely used by Web search engines to index all the pages on a site by following the links from page to page. The search engine summarizes the content and adds the links to their indexes. Spiders are also used to locate Web pages that sell a particular product or to find blogs that have opinions about a product. See spidering program and surface Web.

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Shares in a trust that owns stocks in the same proportion as that represented by the S&P 500 stock index. Due to the acronym SPDR, Standard & Poor's Depository Receipts are commonly known as "spiders". Each share of a spider contains one-tenth of the S&P 500 index, and so trades at roughly one-tenth of the level of the S&P 500. Spiders trade on the American Stock Exchange (AMEX) under the ticker symbol SPY.

Investopedia Says:
SPDRs are exchange-traded funds and, therefore, they trade like ordinary shares on the stock market. By trading like a stock, spiders have continuous liquidity, can be short sold, provide regular dividend payments and incur regular brokerage commissions when traded.

Spiders are used by large institutions and traders as bets on the overall direction of the market. They are also used by investors who believe in passive management - those who don't try to beat the market. In this respect, spiders compete directly with S&P 500 index funds.

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Shares in a trust that owns stocks in the same proportion as the Standard & Poor's 500 stock index. Spiders, also known as Standard & Poor's Depositary Receipts, sell for a dollar amount equal to about one-tenth of the Standard & Poor's 500 index level.

Considering how general is the dislike of spiders, they feature often and have mainly a positive reputation in English lore. The belief that it is unlucky to kill a spider is generally reported: ‘… If you are sweeping, and come on a web, don't destroy it till the spider is safe, when you may sweep away the web; but if you kill the spider it will surely bring poverty to your house’, (Isle of Wright: N&Q 12s:3 (1917), 396). It is still considered lucky if a small spider alights on you, and these are thus generally called ‘money-spiders’ or ‘money-spinners’. To ensure good luck, some believe you must throw the spider over your left shoulder, or, more elaborately, hold the thread by which it is hanging, pass it (and spider) three times round your head, and place the spider back where you found it (N&Q 5s:12 (1879), 229, 254, 277, 295, 518).

One legend which seeks to explain our regard for spiders tells that on the flight into Egypt, when the Holy Family took shelter in a cave, a spider quickly spun its web across the mouth, and a dove laid an egg in the web. The pursuing soldiers thus concluded that the cave had been unused for some time and neglected to search it. This tale has numerous international parallels and is also told of King David and of Mahomet. A different story relates how the spider spun a beautiful web over Christ's manger in the stable (N&Q 169 (1935), 460; 170 (1936) 50, 212, 266, 303; Radford, Radford, and Hole, 1961: 317-18; Henderson, 1879: 312).

Spiders do not fare so well in the realm of folk medicine, as the cure usually results in their death one way or another. A longstanding cure for ague or fever was to imprison a spider, often in a nut-shell, which would be worn as an amulet—Pliny (Natural History (AD 77), xxx) includes this cure, and English writers since at least the 16th century have also recommended it. Similar methods were used for whooping cough. Other cures involve eating the spider, for example as a cure for ague, taken with a spoonful of jam (N&Q 151 (1926), 404). Cobwebs were believed to have medicinal value in themselves. Mixed with bread and made into pills, they were another recommended remedy for the ague at least since the 17th century (N&Q 10s:1 (1904), 205, 273-4, 317-18). There are many who still believe that cobwebs slapped on a wound stop the bleeding.

Bibliography
The full bibliography list is available here.

• Opie and Tatem, 1989: 368-72
• Black, 1883: 58-61
• Lean, 1902: ii) (numerous references, the index in vol. iv is incorrect, referring to vol. i instead of vol. ii)