Components and Peripherals

Component / Peripheral

Description
Picture
1
AC Adapter
AC adapter accept AC input voltage directly from a wall outlet, and output AC voltage
2
AGP Card
Accelerated Graphics Port / Advanced Graphics Port. An expansion bus developed by Intel® specifically for the video card, that was designed specifically for demands of 3D graphics applications.

3
Antiglare Screen
A monitor screen that is treated to reduce glare(Great brightness) from light sources. Non-glare CRTs often use a coating baked onto the screen at the time of manufacture, which provides a significant reduction in glare

4
Barcode Reader
A barcode reader (or barcode scanner) is a computer peripheral for reading barcodes printed on various surfaces. Like a flatbed scanner, it generally consists of a light source, a lens and a photo conductor translating optical impulses into electrical ones.

5
BD Drive
An HD-DVD format that uses a 405nm-wavelength blue-violet laser technology, to be compared with the 650nm-wavelength red laser technology in use in traditional DVD format. The rewritable Blu-ray disc can store up to 25GB of data on a single-sided single layer disc .
6
Blue tooth Adapter
A short distance, low speed radio frequency technology primarily used to allow a Personal Digital Assistant (PDA) or mobile phone to interact with a laptop or desktop computer.

7
Cable MODEM
A cable modem is a special type of modem that is designed to modulate a data signal over cable television infrastructure.
8
Card Reader
A Card reader is an extra piece of hardware which will plug directly into your computer, generally via a USB port and allow you to read the contents of a media card without the need to plug your camera into the PC.

9
Card Scanner/
Business Card Scanner
Card Scanner saves you hours by capturing business cards and contact information directly into your computer.Without typing, you build a database of your vital contacts, either in CardScan's address book, in Outlook, or in any other popular contact manager.
10
CD / DVD Duplicator
A Device that can duplicates CD’s / DVD’s in bulk without the nee for a Computer
11
CD-ROM Drive
CD ROM stands for Compact Disk Read-Only Memory, data on CD ROMs can only be read--not altered--by the user.
12
CD-Writer
A CD recorder, CD writer or CD burner is a compact disc drive that can be used to produce discs readable in other CD-ROM drives and audio CD players
13
CMOS Battery
CMOS (pronounced "see-moss"), which stands for complementary metal-oxide-semiconductor uses 3Volts Lithium battery power to store data. Lithium batteries are primary batteries that have lithium metal anodes.

14
COMBO Drive
A DVD-ROM drive capable of reading and writing CD-R and CD-RW media.
15
Computer CASE /
Cabinet
A computer case (also known as the computer chassis, box or housing) is the enclosure that contains the main components of a computer.
16
Cordless Keyboard
Battery-powered keyboards that send signals with infrared or radio waves, also called "wireless keyboards."


17
Cordless Mouse
Battery-powered Mouse that send signals with infrared or radio waves, also called "wireless Mouse"
18
CPU / Processor
Central Processing Unit / Processor .The brain of the computer - the device capable of performing Arithmetic and Logical operations on data.

19
CRT Monitor
Cathode-ray tube: a vacuum tube Monitor in which a hot cathode emits a beam of electrons that pass through a high voltage anode and are focused or deflected before hitting a phosphorescent screen
20
DC Adapter
DC adapter accept AC input voltage directly from a wall outlet, and output DC voltage
21
Digital Camera
A camera which stores images as digital information rather than on photographic film. This allows images to be easily displayed and edited on computer.

22
Digital Pen
An instrument that captures what the user writes on paper and sends it to the computer. Using special paper with a tiny grid that enables the pen to sense what is actually written or drawn, the device turns the writing into an image file and transmits it to the computer via wireless or when mounted in a cradle.

23
DVD ROM Drive
The DVD-ROM supports disks with capacities of from 4.7GB to 17GB and access rates of 600 KBps to 1.3 MBps. One of the best features of DVD-ROM drives is that they are backward-compatible with CD-ROMs. This means that DVD-ROM players can play old CD-ROMs

24
eBook
"eBook" is short for "electronic book" eBooks can be downloaded and read on an electronic device like a desktop or notebook computer. eBooks are versatile, portable and convenient.
25
Ergonomic Computer Chair
Ergonomic computer chair that has been enthusiastically received by users and applauded by medical and scientific professionals from major institutions.
26
Ergonomic Keyboard
A keyboard that separates the keys into two halves shaped like a wide "V." Some keyboards have a fixed layout, while others are movable. To the touch typist, the layout feels odd at first, but it puts less stress on the hands and wrist and winds up being comfortable for most people.

27
Fiber Optic Cable/
A cable, consisting of a center glass core surrounded by layers of plastic, that transmits data using light rather than electricity. It has the ability to carry more information over much longer distances.

28
FireWire Hub
FireWire hubs provide IEEE 1394 compliant ports that support data transfer rates of 400Mbps and 800 Mbps (megabits per second), and automatically switches to the highest speed that the peripheral supports.

29
Floppy Disk Drive
A drive that reads from or writes to separate diskettes which the user inserts. Information is stored on the diskettes themselves, not on the drive.
30
Game Pad
A pointing device like a mouse used to move an object on a computer screen. A game pad is a flat hand held pad with several control buttons connected tot he computer by a special port. These are most frequently used in computer games
31
Hand Scanner
An optical device used to digitize a relatively small image or artwork.
32
Hard Disk Drive
A hard disk (or "hard disc" or "hard drive" or "hard disk drive") is a computer storage device that stores data on rotating magnetic surfaces.

33
Hardware Lock/
Dongle
A hardware device that plugs into a parallel or a USB port, acting as copy protection for a particular software application.
34
HDD Cradle /
HDD Enclosure
Hard Disk Drive cradle, A container that turns a standard hard drive into a removable one. The hard drive is bolted into a removable carrier that is inserted into a stationary cradle that connects to the power supply and signal cables in the computer case.

35
Heat Sink Compound /
Thermal Compound
A thick gooey substance, with very good heat conductive qualities. This is placed between the CPU core and the surface of the heatsink, to assist in the quick transferal of heat from the core. Having good quality thermal compound can make large differences to your temperatures.

36
Heat sink with Fan
A component designed to lower the temperature of an electronic device by dissipating heat into the surrounding air. All modern CPUs require a heat sink with Fan
37
iPod
The generic brand iPod refers to a class of portable digital audio players designed and marketed by Apple Computer. Most iPod models store media on a built-in hard drive, while a lower-end model, iPod shuffle, relies on flash memory. ...
38
IDE Card
A device that is used to provide IDE, FDD, COM, LPT ports onto old Motherboards / PC’s
39
Infrared Adapter
The USB-IrDA adapter provides a bridge to the USB port of a laptop/desktop PC, allowing high speed 4M bps wireless data transfer for record synchronization, file back-up and network access with IrDA capable cell phones, PDAs, keyboards, digital cameras, scanners and printers .

40
Ink Cartridge
A cartridge that contains ink and can be replaced
41
Internet Sharer
A Device that is used to share a single internet connection onto multiple PC’s
42
Inverter
An appliance used to convert independent DC power into standard household AC current.
43
IRIS pen
The IRIS Pen is a text recognition pen scanner. It instantaneously retypes any printed information in your word processor, e-mail software, on-line databases, etc.

44
Joystick
An input device used for video games and for some graphics applications.
45
Keyboard
An input device consisting of various keys that allows the user to input data, control cursor and pointer locations, and to control the dialog with the Computer workstation.

46
Kiosk
A small, self-standing structure such as a newsstand or ticket booth. Unattended multimedia kiosks dispense public information via computer screens. Either a keyboard, touch screen or both are used for input.

47
KVM Switch
A KVM switch (with KVM being an acronym for Keyboard, Video, Mouse) is a hardware device that allows a user to control multiple computers from a single keyboard, video monitor and mouse.

48
LAN / Ethernet/
Network Card
The Ethernet card provides a standardized way of connecting computers together to create a network.
49
LAPTOP /
Notebook Computer
A laptop computer (also known as notebook computer) is a small mobile personal computer,
50
LCD Monitor
A monitor that uses liquid-crystal display technology. Many laptop and notebook computers use LCD displays because of their low power requirements, lightweight, portable and compact alternative to the CRT monitors.
51
Light Pen
A light-sensitive input device shaped like a pen, used to draw on the computer screen or to make menu selections. As the tip of the light pen makes contact with the screen, it sends a signal back to the computer containing the xy coordinates of the pixels at that point.
52
Magnetic Card Reader
Input device on a card terminal that translates the information stored on the magnetic stripe on the back of a card.

53
Memory / RAM
Abbreviation for Random Access Memory. It is erasable program memory; programs and data are usually copied into RAM from a disk drive. Data in RAM is lost when power is removed.

54
Memory Card/
Flash Memory Card

A storage device used to store data, such as picture and movie files. Available in a range of sizes, such as 8 MB, 32 MB, and 256 MB.
55
Microphone
A microphone, sometimes called a mic (pronounced "mike"), is a device that converts sound into an electrical signal. Microphones are used in many applications such as telephones, tape recorders and Computers

56
MODEM
Modulator/Demodulator, A device that allows two computers to communicate over telephone lines. It converts digital computer signals into analog format for transmission. A similar device at the other end converts the analog signal back into a digital format that the computer can understand

57
Monitor Sharer
A device that is used to share multiple monitors on a single PC.



58
Motherboard/
Mainboard
The main printed circuit board in a computer that carries the system buses. It is equipped with sockets to which all processors, memory modules, plug-in cards, daughterboards, or peripheral devices are connected.

59
Mouse
A pointing device that controls input by moving a cursor or other figure on the screen. Normally, the user points to an object on the screen and then presses a button on the mouse to indicate her selection.

CPU / PROCESSOR

The CPU is the part of a computer in which arithmetic and logical operations are performed and instructions are decoded and executed. The CPU controls the operation of the computer.
Basic structure
A processor's major functional components are:
· Core: The heart of a modern is the execution unit. The Pentium has two parallel integer pipelines enabling it to read, interpret, execute and despatch two instructions simultaneously.

· Branch Predictor: The branch prediction unit tries to guess which sequence will be executed each time the program contains a conditional jump, so that the Prefetch and Decode Unit can get the instructions ready in advance.

· Floating Point Unit: The third execution unit in a Pentium, where non-integer calculations are performed.

· Level 1 Cache: The Pentium has two on-chip caches of 8KB each, one for code and one for data, which are far quicker than the larger external secondary cache.

· Bus Interface: This brings a mixture of code and data into the CPU, separates the two ready for use, and then recombines them and sends them back out.
All the elements of the processor stay in step by use of a "clock" which dictates how fast it operates. The very first microprocessor had a 100KHz clock, whereas the Pentium Pro uses a 200MHz clock, which is to say it "ticks" 200 million times per second. As the clock "ticks", various things happen. The Program Counter (PC) is an internal memory location which contains the address of the next instruction to be executed. When the time comes for it to be executed, the Control Unit transfers the instruction from memory into its Instruction Register (IR).

At the same time, the PC is incremented so that it points to the next instruction in sequence; now the processor executes the instruction in the IR. Some instructions are handled by the Control Unit itself, so if the instruction says "jump to location 2749", the value of 2749 is written to the PC so that the processor executes that instruction next.
Many instructions involve the arithmetic and logic unit (ALU). This works in conjunction with the General Purpose Registers - temporary storage areas which can be loaded from memory or written to memory. A typical ALU instruction might be to add the contents of a memory location to a general purpose register. The ALU also alters the bits in the Status Register (SR) as each instruction is executed; this holds information on the result of the previous instruction. Typically, the SR has bits to indicate a zero result, an overflow, a carry and so forth. The control unit uses the information in the SR to execute conditional instructions such as "jump to address 7410 if the previous instruction overflowed".
This is about all there is as far as a very basic processor is concerned and just about any operation can be carried out using sequences of simple instructions like those described.

The Five Generations of Computers

The history of computer development is often referred to in reference to the different generations of computing devices. Each generation of computer is characterized by a major technological development that fundamentally changed the way computers operate, resulting in increasingly smaller, cheaper, more powerful and more efficient and reliable devices. Read about each generation and the developments that led to the current devices that we use today.

First Generation - 1940-1956: Vacuum Tubes

The first computers used vacuum tubes for circuitry and magnetic drums for memory, and were often enormous, taking up entire rooms. They were very expensive to operate and in addition to using a great deal of electricity, generated a lot of heat, which was often the cause of malfunctions. First generation computers relied on machine language to perform operations, and they could only solve one problem at a time. Input was based on punched cards and paper tape, and output was displayed on printouts.

The UNIVAC and ENIAC computers are examples of first-generation computing devices. The UNIVAC was the first commercial computer delivered to a business client, the U.S. Census Bureau in 1951.

Second Generation - 1956-1963: Transistors

Transistors replaced vacuum tubes and ushered in the second generation of computers. The transistor was invented in 1947 but did not see widespread use in computers until the late 50s. The transistor was far superior to the vacuum tube, allowing computers to become smaller, faster, cheaper, more energy-efficient and more reliable than their first-generation predecessors. Though the transistor still generated a great deal of heat that subjected the computer to damage, it was a vast improvement over the vacuum tube. Second-generation computers still relied on punched cards for input and printouts for output.

Second-generation computers moved from cryptic binary machine language to symbolic, or assembly, languages, which allowed programmers to specify instructions in words. High-level programming languages were also being developed at this time, such as early versions of COBOL and FORTRAN. These were also the first computers that stored their instructions in their memory, which moved from a magnetic drum to magnetic core technology.

Third Generation - 1964-1971: Integrated Circuits

The development of the integrated circuit was the hallmark of the third generation of computers. Transistors were miniaturized and placed on silicon chips, called semiconductors, which drastically increased the speed and efficiency of computers.



Instead of punched cards and printouts, users interacted with third generation computers through keyboards and monitors and interfaced with an operating system, which allowed the device to run many different applications at one time with a central program that monitored the memory. Computers for the first time became accessible to a mass audience because they were smaller and cheaper than their predecessors.

Fourth Generation - 1971-Present: Microprocessors

The microprocessor brought the fourth generation of computers, as thousands of integrated circuits were built onto a single silicon chip. What in the first generation filled an entire room could now fit in the palm of the hand. The Intel 4004 chip, developed in 1971, located all the components of the computer - from the central processing unit and memory to input/output controls - on a single chip.

In 1981 IBM introduced its first computer for the home user, and in 1984 Apple introduced the Macintosh. Microprocessors also moved out of the realm of desktop computers and into many areas of life as more and more everyday products began to use microprocessors.

As these small computers became more powerful, they could be linked together to form networks, which eventually led to the development of the Internet. Fourth generation computers also saw the development of GUIs, the mouse and handheld devices.

Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice reco

Fifth generation computing devices, based on artificial intelligence, are still in development, though there are some applications, such as voice recognition, that are being used today. The use of parallel processing and superconductors is helping to make artificial intelligence a reality. Quantum computation and molecular and nanotechnology will radically change the face of computers in years to come. The goal of fifth-generation computing is to develop devices that respond to natural language input and are capable of learning and self-organization.