A computer is a machine for manipulating data according to a list of instructions known as a program.

Computers are extremely versatile. In fact, they are universal information-processing machines. According to the Church–Turing thesis, a computer with a certain minimum threshold capability is in principle capable of performing the tasks of any other computer, from those of a personal digital assistant to a supercomputer, as long as time and memory capacity are not considerations. Therefore, the same computer designs may be adapted for tasks ranging from processing company payrolls to controlling unmanned spaceflights. Due to technological advancement, modern electronic computers are exponentially more capable than those of preceding generations (a phenomenon partially described by Moore's Law).

Computers take numerous physical forms. Early electronic computers were the size of a large room, and such enormous computing facilities still exist for specialized scientific computation — supercomputers — and for the transaction processing requirements of large companies, generally called mainframes. Smaller computers for individual use, called personal computers, and their portable equivalent, the laptop computer, are ubiquitous information-processing and communication tools and are perhaps what most non-experts think of as "a computer". However, the most common form of computer in use today is the embedded computer, small computers used to control another device. Embedded computers control machines from fighter aircraft to digital cameras.

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Merriam-Webster's Word of the Day

macadam
Sat, 05 Jul 2008 01:15:01 -0500
Merriam-Webster's Word of the Day for July 05, 2008 is: macadam • \muh-KAD-um\  • noun : a roadway or pavement of small closely packed broken stone Example sentence: We left the old city with much regret, passing from its quaint cobblestones to lumpy macadam, leaving our vacation behind and returning reluctantly to the workaday world. Did you know? In 1783, inventor John Loudon McAdam returned to his native Scotland after amassing a fortune in New York City. He became the road trustee for his district and quickly set his inventiveness to remedying the terrible condition of local roads. After numerous experiments, he created a new road surfacing material made of bits of stone that became compressed into a solid mass as traffic passed over them. His invention revolutionized road construction and transportation, and engineers and the public alike honored him by using his name (respelled "macadam") as a generic term for the material or pavement made from it. He is further immortalized in the verb "macadamize," which names the process of installing macadam on a road.
inalienable
Fri, 04 Jul 2008 01:15:01 -0500
Merriam-Webster's Word of the Day for July 04, 2008 is: inalienable • \in-AY-lee-uh-nuh-bul\  • adjective : incapable of being alienated, surrendered, or transferred Example sentence: "Just because I can use my work e-mail for personal correspondence doesn't mean I have the inalienable right to do so," Brian explained. Did you know? "Alien," "alienable," "inalienable" -- it's easy enough to see the Latin word "alius," meaning "other," at the root of these three words. "Alien" joined our language in the 14th century, and one of its earliest meanings was "belonging to another." By the early 1600s that sense of "alien" had led to the development of "alienable," an adjective describing something you could give away or transfer ownership of, and "unalienable," its opposite. By about 1645, "inalienable" was also in use as a synonym of "unalienable." "Inalienable" is the more common variant today, but it was "unalienable" that was used in the Declaration of Independence to describe rights like life, liberty, and the pursuit of happiness.
peregrine
Thu, 03 Jul 2008 01:15:01 -0500
Merriam-Webster's Word of the Day for July 03, 2008 is: peregrine • \PAIR-uh-grin\  • adjective : having a tendency to wander Example sentence: "Birders are peregrine by nature, typically traveling to distant destinations in pursuit of their hobby. . .." (James F. McCarty, Plain Dealer [Cleveland], June 1, 2006) Did you know? The current meaning of "peregrine" has wandered a bit from its earlier meanings. The word originally meant "foreign," as did its Latin predecessor "peregrinus." But even before "peregrine" appeared on its own in English, it was part of the name of that well-known bird of prey, the peregrine falcon. The bird's appellation derives from "falco peregrinus" -- literally, "pilgrim falcon" in Medieval Latin. Peregrine falcons typically nest in high places, such as on cliff ledges or, in modern times, city skyscrapers. Because of the nests' inaccessibility, medieval falconers who wanted young peregrine falcons to train had capture them on their first flights or migratory "pilgrimages." That practice led to a new sense of "peregrine" ("engaged in or traveling on a pilgrimage"), which was later broadened to "wandering."
reify
Wed, 02 Jul 2008 01:15:01 -0500
Merriam-Webster's Word of the Day for July 02, 2008 is: reify • \RAY-uh-fye\  • verb : to regard (something abstract) as a material or concrete thing : to give definite content and form to (something abstract) Example sentence: "He describes the phenomenal popularity of Edwin Markham's proletarian poem 'The Man With the Hoe,' which reified labor's feelings of injustice." (Neal Gabler, The Washington Post, February 18, 1996) Did you know? "Reify" is a word that attempts to provide a bridge between what is abstract and what is real. Fittingly, it derives from a word that is an ancestor to "real" -- the Latin noun "res," meaning "thing." Both "reify" and the related noun "reification" first appeared in English in the mid-19th century, though "reification" is a few years older and some dictionaries consider "reify" to be a back-formation of the noun. In general use, the words refer to the act of considering or presenting an abstract idea in real or material terms, or of judging something by a concrete example.
trichotillomania
Tue, 01 Jul 2008 01:15:01 -0500
Merriam-Webster's Word of the Day for July 01, 2008 is: trichotillomania • \trick-uh-till-uh-MAY-nee-uh\  • noun : an abnormal desire to pull out one's hair Example sentence: Connie's trichotillomania left her with an unfortunate array of bald spots along the crown of her head. Did you know? The word "trichotillomania" derives from the Greek "trich-" ("hair") and "tillein" ("to pull or pluck"), along with the suffix "-mania" (from "mainesthai," meaning "to be mad"). People suffering from trichotillomania will routinely pluck hair from the scalp, eyebrows, eyelashes or other parts of the body, usually impulsively but sometimes with careful deliberation (such as by using tweezers). Some researchers believe that it may be a form of obsessive-compulsive disorder. The word for this condition first appeared in English around the dawn of the 20th century (it's generally thought to have been first coined in French by a French dermatologist).
decimate
Mon, 30 Jun 2008 01:15:01 -0500
Merriam-Webster's Word of the Day for June 30, 2008 is: decimate • \DESS-uh-mayt\  • verb 1 : to take or destroy the tenth part of *2 : to cause great destruction or harm to Example sentence: Farmers struggled to feed their families after their crops were decimated by blight. Did you know? The connection between "decimate" and the number ten harks back to a brutal practice of the army of ancient Rome. A unit that was guilty of a severe crime (such as mutiny) was punished by selecting and executing one-tenth of its soldiers, thereby scaring the remaining nine-tenths into obedience. It's no surprise that the word for this practice came from Latin "decem," meaning "ten." From this root we also get our word "decimal" and the name of the month of December, originally the tenth month of the calendar before the second king of Rome decided to add January and February. In its extended uses "decimate" strayed from its "tenth" meaning and nowadays refers to the act of destroying or hurting something in great numbers. *Indicates the sense illustrated in the example sentence.

MedTerms Word of the Day

Queensland tick typhus
Sat, 05 Jul 2008 00:00:00 -0700
Queensland tick typhus: One of the tick-borne rickettsial diseases of the eastern hemisphere. Queensland tick typhus is similar to Rocky Mountain spotted fever, another tick-borne rickettsial disease, but is less severe. The clinical features of Queensland tick typhus include fever, a small ulcer (eschar) at the site of the tick bite, swollen glands nearby (satellite lymphadenopathy), and a red raised (maculopapular) rash. Rickettsia such as that responsible for Queensland tick typhus are odd microorganisms. Like viruses, they have to live within other cells to survive. But like bacteria, rickettsia use oxygen, have metabolic enzymes and cell walls, and are susceptible to antibiotics. MedTerms (TM) is the Medical Dictionary of MedicineNet.com.We Bring Doctors' Knowledge To You

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