worm

The French Polynesian Christmas tree worm. Sometimes called spiralled fan worms, Christmas tree worms live in limestone tubes permanently attached or embedded in coral rock. Their radioles, the hairlike appendages radiating from the central spine, are used to catch phytoplankton floating in the water.

Any of various elongated, limbless invertebrates belonging to several phyla. Worms include the flatworms, such as flukes and tapeworms; the roundworms or nematodes, such as the eelworm and the hookworm; the marine ribbon worms or nemerteans; and the segmented worms or annelids.

In 1979, giant sea worms about 3 m/10 ft long, living within tubes created by their own excretions, were discovered in hydrothermal vents 2,450 m/8,000 ft beneath the Pacific northeast of the Galapagos Islands.

A new species of polychaete worm was discovered in 1997 on the floor of the Gulf of Mexico. It is a pink centipedelike worm that is about 5 cm/2 in long and lives in highly populated colonies in methane ice.

WORM

In computing, a storage device, similar to a CD-ROM. The computer can write to the disk directly, but cannot later erase or overwrite the same area. WORMs are mainly used for archiving and back-up copies.

worm

In computing, virus designed to spread from computer to computer across a network. Worms replicate themselves while ‘hiding’ in a computer's memory, causing systems to ‘crash’ or slow down, but do not infect other programs or destroy data directly.

The most celebrated worm was the ‘Internet worm’ of November 1988. Released onto the Internet by Robert Morris, Jr, a graduate student at Cornell University, it infected some 6,000 systems via a loophole in Unix e-mail and finger procedures. Morris claimed that a programming bug had caused the worm to replicate far more virulently than he had intended, and took swift measures to publish an ‘antidote’ on the network – but by then, many machines had already been disconnected from it. Morris was later convicted, fined, and sentenced to 400 hours community service.

In the early years of the 21st century, the Internet was plagued by a number of worms, including Melissa, LoveBug, Slammer, SoBig, Blaster, MyDoom, and Netsky.