what is a computer?

computerRelated Terms*.PC - personal computer*.PC - personal computer*.personal computer game*.home computer*.network computer*.MPC*.Apple Computer*.pervasive computing*.computer business*.end-user computingByVangie BealA computer generally meansa programmable machine. The two principal characteristics of a computer are: it responds to a specific set ofinstructionsin a well-defined manner and it canexecutea prerecorded list of instructions (aprogram).Modern Computers DefinedModern computers are electronic anddigital. The actual machinery—wires,transistors, and circuits—is calledhardware; the instructions anddataare calledsoftware.ThinkCentre® Tiny-in-One 23 NASCAR ChallengeDownload NowAll general-purpose computers require the following hardware components:*.Memory:enables a computer tostore, at least temporarily, data and programs.*.Mass storagedevice:allows a computer to permanently retain large amounts of data. Common mass storage devices includedisk drivesandtape drives.*.Input device:usually akeyboardandmouse, the input device is the conduit through which data and instructions enter a computer.*.Output device:adisplay screen,printer, or other device that lets you see what the computer has accomplished.*.Central processing unit(CPU):the heart of the computer, this is the component that actually executes instructions.In addition to these components, many others make it possible for the basic components to work together efficiently. For example, every computer requires abusthat transmits data from one part of the computer to another.Computer Classification: By Size and PowerComputers can be generally classified by size and power as follows, though there is considerable overlap:*.Personal computer:a small, single-usercomputer based on amicroprocessor. In addition to the microprocessor,a personal computer has a keyboard for entering data, amonitorfor displaying information, and astorage deviceforsavingdata.*.Workstation:a powerful, single-user computer. A workstation is like a personal computer, but it has a more powerful microprocessor and a higher-quality monitor.*.Minicomputer:amulti-usercomputer capable of supporting from 10 to hundreds of users simultaneously.*.Mainframe:a powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously.*.Supercomputer:an extremely fast computer that can perform hundreds of millions of instructions per second.The First ComputerThe first computer, the ENIAC machine (John W. Mauchly and J. Presper Eckert at the University of Pennsylvania) used 18,000 vacuum tubes and trequired 167 square meters (1800 square feet) of floor space (source). PREVIOUScomputeNEXTcomputer animationRelated Links*.What Is 64-bit Computing?*.Getting Started With Green Computing*.Microprocessor Comparison Chart*.Timeline of Computer HistoryTECH RESOURCES FROM OUR PARTNERSIaaS Reference Architectures: for AWSState Of FraudThe Critical Need for Endpoint Data ProtectionWe RecommendDatamation Hangouts with Tech ExpertsWatch Datamation's editor James Maguire moderate roundtable discussions with tech experts from companies such as Accenture, Dell, Blue Jeans Network, Microsoft and more »DID YOU KNOW?5 Best Valentines Day Ideas for Open Source RomanticsBecause nothing says "I Love You" Like an open source app.Read More »Guarding your Data against Cyber AttacksIn this new era of heightened stakes comes an increased need for a comprehensive security strategy. Let's take a look at how cyber-threats have...Read More »The Great Data Storage Debate: Is Tape Dead?Tape clearly is on the decline. But remember, legacy systems can hang for a shockingly long time.Read More »QUICK REFERENCENetwork Fundamentals Study GuideA network is a group of two or more computer systems or devices, linked together to share resources, exchange files and electronic communications....Read More »Computer Architecture Study GuideThis Webopedia study guide describes the different parts of a computer system and their relations.Read More »Webopedia PollsThe trend for the past two years has been for shoppers to spend more online during the holiday season. How do you typically shop for holiday...Read More »