Computer <br />BY ROSHAN GURUNG <br /></NOSCRIPT> <br />A programmable machine. The two principal characteristics of a computer are: <br /> It responds to a specific set of instructions in a well-defined manner. <br />It can execute a prerecorded list of instructions (a program). <br />Modern computers are electronic and digital. The actual machinery -- wires, transistors, and circuits -- is called hardware; the instructions and data are called software. <br />All general-purpose computers require the following hardware components: <br /> HYPERLINK "
memory : Enables a computer to store, at least temporarily, data and programs. <br /> HYPERLINK "
mass storage device : Allows a computer to permanently retain large amounts of data. Common mass storage devices include disk drives and tape drives. <br /> HYPERLINK "
input device : Usually a keyboard and mouse, the input device is the conduit through which data and instructions enter a computer. <br /> HYPERLINK "
output device : A display screen, printer, or other device that lets you see what the computer has accomplished. <br /> HYPERLINK "
central processing unit (CPU): The heart of the computer, this is the component that actually executes instructions. <br />In addition to these components, many others make it possible for the basic components to work together efficiently. For example, every computer requires a bus that transmits data from one part of the computer to another. <br />Computers can be generally classified by size and power as follows, though there is considerable overlap: <br /> HYPERLINK "
personal computer : A small, single-user computer based on a microprocessor. In addition to the microprocessor, a personal computer has a keyboard for entering data, a monitor for displaying information, and a storage device for saving data. <br /> HYPERLINK "
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. <br /> HYPERLINK "
minicomputer : A multi-user computer capable of supporting from 10 to hundreds of users simultaneously. <br /> HYPERLINK "
mainframe : A powerful multi-user computer capable of supporting many hundreds or thousands of users simultaneously. <br /> HYPERLINK "
supercomputer : An extremely fast computer that can perform hundreds of millions of instructions per second.<br />CPU <br />Last modified: Thursday, May 28, 2009 <br />Abbreviation for central processing unit, and pronounced as separate letters. The CPU is the brains of the computer. Sometimes referred to simply as the central processor,but more commonly called processor, the CPU is where most calculations take place. In terms of computing power, the CPU is the most important element of a computer system. <br />On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single chip called a microprocessor. Since the 1970's the microprocessor class of CPUs has almost completely overtaken all other CPU implementations. <br />The CPU itself is an internal component of the computer. Modern CPUs are small and square and contain multiple metallic connectors or pins on the underside. The CPU is inserted directly into a CPU socket, pin side down, on the motherboard. Each motherboard will support only a specific type or range of CPU so you must check the motherboard manufacturer's specifications before attempting to replace or upgrade a CPU. Modern CPUs also have an attached heat sink and small fan that go directly on top of the CPU to help dissipate heat. <br />Two typical components of a CPU are the following: <br />The arithmetic logic unit (ALU), which performs arithmetic and logical operations. <br />The control unit (CU), which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.<br />Chip <br />Last modified: Tuesday, January 06, 2004 <br />A small piece of semiconducting material (usually silicon) on which an integrated circuit is embedded. A typical chip is less than ¼-square inches and can contain millions of electronic components (transistors). Computers consist of many chips placed on electronic boards called printed circuit boards. <br />There are different types of chips. For example, CPU chips (also called microprocessors) contain an entire processing unit, whereas memory chips contain blank memory. <br />Chips come in a variety of packages. The three most common are: <br /> HYPERLINK "
DIPs : Dual in-line packages are the traditional buglike chips that have anywhere from 8 to 40 legs, evenly divided in two rows. <br /> HYPERLINK "
PGAs : Pin-grid arrays are square chips in which the pins are arranged in concentric squares. <br /> SIPs : Single in-line packages are chips that have just one row of legs in a straight line like a comb. <br />In addition to these types of chips, there are also single in-line memory modules (SIMMs), which consist of up to nine chips packaged as a single unit. <br />Hardware<br /> Adapters/Cards Buses Connectors, Plugs and Sockets Data Storage Hardware Companies Input Devices Integrated Circuits (ICs) Keyboards Memory Mice Microprocessors Modems Monitors Motherboards Networking Hardware Output Devices Performance Peripheral Devices Ports and Interfaces Printers<br /> 3D Stereo technology 4-way server 8-way server accelerator board ACHA adapter ADC add-in add-on after sales support air cooling AMD Virtualization amplifier repeater AMR ANI HYPERLINK "
anticipointment antistatic mat architecture assistive technology ATA atomic operation ATX automatic test equipment autosense HYPERLINK "
Avivo HD AWT backplane backward compatible bank bare metal barebones bare-metal programming battery pack Bernoulli disk drive bezel BGA Big Iron blank-off plate boot sequence BRS Btu BTX build to order bunny suit burn in bus candela capacitive keyboard HYPERLINK "
CapEx card CELP Certified Wireless USB chassis chassis intrusion connector chip chip creep chips and salsa chipset clamping voltage clean room clock gating Close to Metal CMOS CNR COAST codename combo drive command queuing and reordering HYPERLINK "
CompactFlash compatible computer cabinet computer rack computer system cooling configuration contact image sensor COTS CPE creeping featurism C-RIMM HYPERLINK "
crippleware customer support DDR-SDRAM default gateway device device manager Device Software Optimization device-dependent die dielectric digital access and cross-connect system (DACS) direct memory execute disk image DOCSIS dongle DSO dual head card DVI to VGA adapter DVI-I early adopter edge connector electronic book HYPERLINK "
eSATA expansion board expansion slot external data bus HYPERLINK "
fabless fault tolerance FC-PGA firmware flatbed scanner footprint forklift upgrade form factor HYPERLINK "
Frankenpine fried FRU future-proof GBIC GDDR gender changer glass house GPU GPU clock granularity gray market HAL hardware Hardware Compatibility List heat sink heat spreader HIPS HLF hold-up time host bus hot aisle/cold aisle HWID ICH id10t error IDF IHV HYPERLINK "
iLO iMac in-circuit emulator install integrated integrated peripheral Intel Virtualization Technology Intelligent Platform Management Interface interconnect internal bus internal data bus intrusion prevention system IPS Itanium jukebox kernel32.dll keyboard wedge kill switch KVM switch HYPERLINK "
Larrabee laser-marked keycap latency latency setting LDCM LED legacy device lithography HYPERLINK "
liveware LLF logic gate LOM loopback plug massive array of idle disks master/slave MCH MCU MDF memory bus mode modular architecture Molex MOSFET MRAM multiplier lock multi-port memories Native Command Queuing HYPERLINK "
netbook NGMA NIPS nit Northbridge NTU obsolete OEM oscillator clock OUI output pad-printed keycap patch cord patch panel PDU PEBCAK pedestal server Pentium 4 peripheral device personal Internet communicator PFC physical drive physical erase unit PIA PIC picnic HYPERLINK "
picoJava pixel pipelines Pixel Shader platter PLCC PLD plug compatible plug-and-play plug-in power brick power conditioner power cycling power down power factor correction power supply power up power-on self test PPGA printed circuit board PSOP PSU HYPERLINK "
punchdown block HYPERLINK "
PureVideo HYPERLINK "
PureVideo HD HYPERLINK "
quiesce QVL rack and stack HYPERLINK "
rackmount raised floor real printer real-time clock rectifier redundant refurbished reset button reverse Hyper-Threading RILOE II RIMM riser card RMA router routing switch RTM SATA II seat secondary memory Serial ATA server server blade server cage area set-top box HYPERLINK "
shader shadow mask shock rating shut down SIMM HYPERLINK "
SiS HYPERLINK "
skunkworks slave SLI HYPERLINK "
slimline model HYPERLINK "
Slingbox slot HYPERLINK "
slotket smart card HYPERLINK "
SoC SOE software cooling SOI SOIC solid state disk SOP Southbridge spindle split backplane SPOF spot cooling SSOP stand-alone Standard Operating Environment stereoscopic imaging strain relief structural hazard HYPERLINK "
SuperSpeed USB surface-mount technology surge protector Suspend-to-RAM switch system bus system resource system unit system weight TC TCQ thermal compound through-hole technology HYPERLINK "
TnL toaster TPM travel weight troubleshoot HYPERLINK "
TrueFFS TSOP tutorial HYPERLINK "
twinaxial cable U3 smart drive UMA unified driver upgrade UPS upward compatible USB USB 3.0 USB card reader USB flash drive USB Flash Drive Alliance USRT UVD video adapter voltage regulator Von Neumann machine VRM VSB wafer Wake-on-LAN warm-up time watchdog WfM WHQL Windows Image Acquisition wireless bridge WOL wrapper XLR Y-Cable ZIF socket zoned-bit recording<br />Software <br /> Applications Browsers Business Presentation Communications Software Databases Desktop Publishing Graphics Software Groupware Networking Software Software Companies Spreadsheets User Interfaces Word Processing<br /> HYPERLINK "
abandonware ABEND academic retail software Access Level Ace of Penguins ActiveX add-in add-on adware After Power Failure after sales support ALM Aloha Ambient Air Temperature Android platform Android SDK anti-adware antivirus program HYPERLINK "
Aperi Aperture Size app application Application Lifecycle Management architecture assistive technology Association of Shareware Professionals AUP authoring tool Authorized Education Reseller auto dialer Automatic Fan Detection backward compatible HYPERLINK "
bagbiter bake-off Bayesian filter bells and whistles beta test binary compatible HYPERLINK "
Binutils BIOS flash utility HYPERLINK "
bloatware bootleg build build to order bundled software HYPERLINK "
careware Carnivore Castanet HYPERLINK "
censorware CFML chips and salsa HYPERLINK "
chroma key chromatic aberration clean install client access license COCOMO codename COE ColdFusion commercial software compatible component software configuration HYPERLINK "
configurator configure container content management system copy protection corporate software piracy COTS counterfeit software courseware creeping featurism HYPERLINK "
crimeware crippled version HYPERLINK "
crippleware Cupcake customer support CVS HYPERLINK "
Dalvik HYPERLINK "
DashPC data miner day forward DDMS DD-WRT debug debugger derived works Device Software Optimization device-dependent digital wallet disk scrubbing document flip HYPERLINK "
dribbleware DSI DSO DV converter DVD Studio Pro HYPERLINK "
easter egg Eclipse ECM EDA EDM EFM EII Enterprise Collaboration Systems ECS Enterprise Content Management Enterprise Feedback Management ESRB EULA event exploit Extreme Programming false positive fatal exception error feature feature creep File Scripting Object Final Cut Pro firmware forms processing forms software freeware Full Packaged Product full retail software functional specification gold version Google Docs and Spreadsheets Google Office gray market HYPERLINK "
greyware HAL hard disk loading HYPERLINK "
haxie HIPS HYPERLINK "
hotfix HTML converter HTML editor HTTPD HYPERLINK "
HyperOffice hypervisor id10t error IEEE 829 in-circuit emulator Industry Foundation Classes install integrated Internet software piracy intrusion detection system intrusion prevention system HYPERLINK "
iPhone SDK HYPERLINK "
JavaSpaces jewel case software HYPERLINK "
Jini JMS JNI HYPERLINK "
Joomla HYPERLINK "
JumperFree configuration keyboard wedge HYPERLINK "
keylogger kill switch killer app kiosk browser L0phtCrack HYPERLINK "
liveware LLDP Agent Longhorn m0n0wall machine dependent machine independent HYPERLINK "
MacVCD Mambo HYPERLINK "
Metasploit Microsoft Access Microsoft Volume Licensing middleware minimum system requirements HYPERLINK "
mIRC MIS mode modular architecture MTA MUA MVC HYPERLINK "
mWare HYPERLINK "
nagware Napster native code Nero NIPS OA OEM OEM unbundling office automation HYPERLINK "
omnifont recognition on-demand software delivery online editing open source Open Source Initiative Oslo patch PEBCAK personal finance manager phone home picnic plug-in HYPERLINK "
polyfont recognition portable portal application predictive dialer premastering project portfolio management proprietary software public-domain software PUP HYPERLINK "
PuTTY PWS QT Mutator recommended system requirements redundant refactoring regression testing reimage Retail Software License Terms robust RTM RUP HYPERLINK "
SaaS sales force automation SCM screen scraper SDLC seat security information management self-extracting file semi-free software service pack shareware SIEM SIM site license HYPERLINK "
skunkworks slipstream SLOC Snort SOE HYPERLINK "
softlifting software software cooling software entropy software environment software licensing software package software piracy Software Quality Assurance HYPERLINK "
SoSaaS HYPERLINK "
spamware speech synthesis SPOF spyware Standard Operating Environment static testing Subversion HYPERLINK "
subweb support system requirements system resource Task Manager TCP Wrapper test-driven development HYPERLINK "
Tinn HYPERLINK "
TMPGEnc TOAD toaster tool trial Tru64 TSCV tutorial UAT unified driver UP upgrade upward compatible HYPERLINK "
USBlyzer vaporware HYPERLINK "
VCDimager HYPERLINK "
Vdub viewer virtual honeypot virtual network computing HYPERLINK "
VirtualDub Vista SP1 HYPERLINK "
vNAS HYPERLINK "
vSERV vulnerability scanning War FTP Daemon HYPERLINK "
warez watchdog Web authoring Web stack HYPERLINK "
Websphere HYPERLINK "
Webware Windows Image Acquisition wrapper HYPERLINK "