Input, Out and Processing

Computer Literacy BASICS: A Comprehensive Guide to IC3, 3rd Edition, page: Mod1-27

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Page 7 of 10User: Ali Kaba

LESSON 2

Input, Output, and Processing

OBJECTIVES Upon completion of this lesson, you should be able to:

Ident ify and describe standard and specialized input devices. Ident ify and describe standard and specialized output devices. Ident ify and describe how input and output devices are connected

to the computer. Consider computer performance factors.

DATA FILES You do not need data files to complete this lesson.

Q) Estimated Time: 2 hours

VOCABULARY audio input biometrics digita I camera expansion slot FireWire inkjet printer input keyboard laser printer modem monitor mouse

output plug-and-play pointing device port printer scan ner

trackball Universal Seri al Bus (USB)

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~ VOCABULAR Y input

key boa rd

@ EXTRA FOR EXPERTS Need more space on your desk? Consider the Near ly Indestructible Keyboard {N!K)- it is flexible, can be rolled up and put into a brief-case, and even washed with soap and water or a spray cleaner (www. dovecoteglobal. comlnik. fltmn.

MODULE 1 Computing Fundamentals

When it comes to processing data, it is the computer that does all of the work. However, it need, help. II/Pil i , wh.ich is data or instructions, must be entered into the computer and then stored temporarily or permanently on a storage media device. To tum the data into inform.ation. it must be processed. The central processing unit (C PU). which you learned about in Lesson I. processes tbe data . After the data is processed. it is ",Presented" to the user through an output device.

Standard Input Devices Input devices cmlble you to enter data and commands into the computer, and output deyices enable the computer to give you the results of the processed data. Some devices perfonn both input and output functions, slich .as the fax machine and fax modem. You use these devices to send (outpUI) ;:Ind receive (input) data over communications media.

The type of input device you use is determined by the task you need to complete. An input device can be as simple as the keyboard or as sophisticated as those used for specialized applications such as voice or retinal recognition.

Keyboard The keyboard is the mosl commonly used input device for entering IlLII1leric and alphabetic data into a computer. Lf you are going to use the compuler etlicielltly, it is impommt that yOlt learn to type. Most of the keyboards provided with desktop com pll ters are enhanced. An enhanced keyboard has 12 function keys .along the lOp, two All keys, two Clrl keys. and a set of directional/arrow keys between the typing area and the numeric keY]Jad.

Some keyboards. sllch as the one shown in Hgure 2-1, have multimedia hot keys that enable you to access e-mail and the Internet, adjus;t speaker volume. and have other features such as:l zoom slider. This device makes it easy to zoom in for a closer look .at documents, spreadsheets, pictures, maps, and Web pages .

FIGURE 2- 1 Enhanced keyboard

Not all keyboards. however, are traditional. Some other popular types of keyboards arc:

Ergonomic: This type of keyboard is designed to provide users with more natural. comfortable hand. wrist. and ann positions.

Cordll!Ss or wireless: TIlis is .a battery-powered keyboard that trallsmits data using wircle~s technology.




LESSON 2 Input, Output, and P,oce"ing

Speciali:ed: This keyboard h::t.




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VOCABULARY pointing devic~ mouse


Pointing Devices A p oilltillg device is an input device th~ll allows you to position the pointer on the screen. TIle pointer Gill have scveml shapes, but the most common is an arrow. You use a pointing dc\"ice to move the pointer: select objects, such as text or graphics: and click buttons. icons, menu items, and links. The following sections discuss several pointing devices.

Mouse The //IO llse is the most commonly used poiming device for personal computers. Jt moves on a flat surface and controls the pointer on the screen. TIle mouse fits conve-niently in the palm of your hand. You can use any of the following fouT types of mice:

Mechanical: This type of mouse has a ball located on the bottom that rolls around on a flat surface as the mouse is moved. Sensors inside the mouse deter-mine the direction and distance of the movement. A mouse pad genemlly is used wi th a mechanical mouse.

OpTOlIlecJumica/: This mouse is the same as a mechanical mouse, but uses opti-cal sensors to detect motion of the ball.

Optical: An optical mouse (see Figure 2-511) uses a laser to detect tbe mouse' s movem ent. 0 p1iclll mice h ave no mechanic al moving part~. T hey responrl more q uickly and precisely than mechanical and optomechanical mice.

Wirde.~s: A wLrelcss mouse (see Figure 2-Sb) is a battery-powered device that relies on infnred or ntdio waves to communicate with the computer.

Receiver

(al (bl FIGURE 2-5 (a) Optical mouse (b) Wireless mouse and receiver

Most miee have two or three buttons; some have a wheel. You use the left button for most mouse opemtions. Genemlly, clicking the right button d isplays a shortcut menu. After you pl.ace the on-screen pointer where you want it, press a button on the mouse. This causes some type of action to take place in the computer: the type of act ion depends on the program. Use the wheel to scroll or zoom a page.

You use the mouse to accomplish the followi ng techniques in most software programs and Web pages:

Poimillg: Plac ing the oil-screen pointer at a designated location Clicking: Pressing and relcasing the mOllse button to select a specific location

within a document Draggil1g: Pressing down thc mouse button and moving the mouse whilc

continuing to hold down the button to highlight :I. selected portion of text




LESSON 2 Input, Output, and Processing

Double-clicking: Pressing and releasing the mouse button two times in rapid succession to select a word

Triple -clicking: Pressing and releasing the mouse button three times in rapid succession to select a paragraph

Right-clicking: Pressing the right mouse button to display a menu Rorate I'i"'heei: Rotate wheel forward or backward to scroll vertically Tilt wheel: Press the wheel right or left to scroll horizontally

Trackball The IrackbaJ[ is a pointing device that works like a mouse turned upside down: the ball is on top of the device. See Figure 2-6a. You usc your thumb and ringers \0 operate the ball, thus controlling the pointer on the screen. A trackbal l is a stationary de ... ice and is a good altemative to the mouse whcn you nave limitcd desktop space. Some trackballs arc built into the keyboard. See Figure 2-6b.

lal Ibl FIGURE 2- 6 (a) Trackball on a mouse (b) Trackball on a keyboard

Touchpad A common feature on l.aptop computers is tbe touchpad. a pointing device wiib a specialized surface that can conven the motion and position of your fingers to a rel(Jtive position on screcn. Touchpads are a common femme of laptop computers and can be fou nd on personal digital assistants (PDAs) and ponable media players.

Pointing Stick Many notebook computers contain a pointing stick- a pressure-sensitive device that looks like a penc il erascr. It is located on the keyboard. generally betwecn tne C. H. and B keys. See Figure 2-7. It is moved with the forefinger, while the tnumb is used to press related keys. In a confi ned space. a lot of people find 11 pointing stick more convenient than a mousc. IBM popu larized tbis device by introducing the TrackPoi nl on its 1l1inkPad notebooks.

VOCABULARY Inlckball

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IJ VOCABULARY audiu input output

monitor

~ 11.1 .5


FIGURE 2-7 Pointing stick

Audio Input Audio il/pllt is the process of inputting sound into the computer.TIlis could include speech, sound effects. and music. Audio input devices include microphones. COl DVD players. radios. and other hardware such as electronic kcytmards. Voice input is a category of audio input. Voice-recognition devices are used to "speak" commands into the computer and to ellier text. These devices usually are micropbones. The computer must have some lype of voice-recognition software installed before you can use a yo ice-recognition device. Directory assisHUlce is a type ofyoicc-rccognition technology. as ar~ devices that dis:lbled persons use to command wheelchairs and other objects that make them more mobile.

Standard Output Devices Olltput is data that has been processed into a useful format. Examples of output are printed text, spoken words, music, pictures, video, or graphics . The most common output devices arc monitors and printers. Output devices display information.

Monitors Desktop computers typi ca lly use a monitor as their display device. The screen is part of the monitor, which also includes the housing for its electrical components. Screen output is called soft copy because it is temporary.

Computer mOllitors come in many varieties. The cathode ray tube (CRT) was one of the earliest types of mon itors. This type of monitor is similar to a standard televisioll and can be either monochrome or color. A monochrome monitor screen has a one-color display. which can be whjte. green, or amber. Most of today's monitors are color monitors, which display thousands of colors. CRT monitors are available in various sizes, with the more common being 17-, 19-, and 21 -inch. See }"igure 2-8




LESSON 2 Input, Output , and Processing

Gas plasma technology consists of a tiny amount of gas that is activated by an electrieal charge. See F igure 2-8c. The glls illuminntcs mini.aturc colored f1uores-ccnt lights arranged in a panel-like screen. These monitors have a brilliant color display and are available in sizes up to 60 inches or more.

la) (b) (e) FIGURE 2-8 (a) CRT (b) LCD panel (e) Gas plasma display

Printers Pri"ter~ arc used to produce a paper or hard copy of the processing results. Printer output is called hard copy because it is pemlanent. Several types ofprintcrs arc avail-able. with significant differences in speed. print quality. price, and special feature.s

When selecting a printer, consider the following features:

Speed: Printer speed is measured in pages per minute (ppm). The number of pages a printer can print per minute varies for text and for graphics. Graphics print more slowly than regular text.

Prim qualiTY: Prillt quality is measured in dots per inch (dpi). The higher the dpi. the higher the resolution or print qualit y.

Price: The price includes the original cost of the printer as well




MDdl-34

VOCABULARY illkjet printer


guide rollers

SIMMs (RAM)

Fixi ng ,"1111''''; ~~

Input paper __ cassette

Printing process

The laser beam ~etches' the image on a photosensitive drum. The developing cylinder picks up a fine blacl: powder ca lled toner, which is attracted t o the etched image on the surface of the drum. When the paper comes into contact with the drum holding the image, the toner is transferred to the paper, creating the image 01 the page.

Output tray beam

1~ __ --:::::: ____ TO""catridge

Paper handl ing

Mosllaser primers allow paper to be fed either automatically or manually. Manual feed ing allows envelopes, heavier paper, and nonstandard sizes of paper to be used .

Manuill feed picKup roller

Controlling the printer

While laser printers usually include a control panel, most of the controlling of the printing process is done from the computer by softwa re.

FIGURE 2-9 Howa laser printer works

Inkjet Printers An illkjet primer provides good-quality color printing for less expense tllan a laser printer. See Figure 2-10. Inkjet printing, like laser printing, is a nonimpact process. Ink is squirted tiom nozzles as they pass over the media. Unlike earlier vcrsions of the inkjel printer , newer versions can use regular photocopy papcr.





Input tray Contro l panel

Output tray

Printing process During ptinting, the paper passes below 1he carriage, which holds the ink ca rtridges and print head. As the carri.age moves back and forth over the paper, ink is sprayed in minute droplets onto the page.

Paper and Ink Inkjet printers use single sheets of paper. Since plain paper can be too absorbent for inkjets, manufacturers recommend special ink jet paper, w hich has a

~ arder surface.

FIGURE 2-10 How an in kjet pri nter works

Speakers

Carriage

Controlling the printer The contro l panel includes the oni off switch, an online button, and an LCD panel that displays messages and menus.

Speakers are also a type of output device . Spe akers and headsets generate sound, such as mmic or ins tructions on how to complete a tutorial. Individuals use headsets o r earphones to hear the music o r other voice output privatel y.

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Modl -36

VOCABULARY digital Cllmem

@ EXTRA FOR EXPERTS

1-1. 1.6

You do not need a digital camera to have digital pictures. Many photo labs can deliver photos via the Internet or on a disc in digital format.


Specialized Input Devices A variety of other input devices arc also available, most of which are used for specialized applications. The following section describes these input devices.

Digital Cameras The pictures taken with a digital call/era arc stored digitally and then transferred to the computer's memory. Digital cameras usc a variety of storage media to store the images, including flash memory cards, memory sticks, USB keys, mi lll~d i scs, and other solid-state storage devices. After the pictures are transferred to the computer. they can be viewed quickly and any imperfections can be edited with photo-editing software.

Video input is the process of capttlring full -Illotion images with a type of video camera and then saving the video on a storage medium such as a hard drive, CD, or OVD. After the video is saved, you can view .and edit it. A digital video (DV) camera records video as digital signals: some cameras also capture still images, Some are just a little klrger than 11 crcdjt card. See . ' igure 2-11 . A PC video camera is 3typc of digital video camera that allows the user to send live images over the internet. make video telephone calls. and send e-mail messages with video attachments.

FIGURE 2- 11 Miniaturized digital video camera

Webcams arc video-capillring camems th~lt are connected to computers or to computer networks and display images through the World Wide Web. Generally. these c.ameras arc used for videocollferencillg 3nd or monitoring. WebC:UliS are also used for security purposes. monitoring both movement and sound.

Game Controllers The joystick Rnd wheel are types of pointing devices. Joysticks and wheels, such as the ones shown in Figure 2-12, most often Rre used for games. Thejoystick consists of a plastic or metal rod mounted on a base. You can move thc rod in any direction. Some joysticks have switches or buttons that c an input data in an onfoff response. A wheel is a steering-wheel type of device used to si mulate driving a vehicle. Most wheels also include foot pedals used for braking and acceleration ~lctiom.





I') Ib) FIGURE 2-12 (a) Joyst ick (b) Wheel

Scanners/ Bar Code Readers Sea/m en are devices that can change image.." into codes for input to the computer. Scanners are available in various sizes and lypeS, including Ihe following:

III/age scanller.~: These devices convert images into an elcctronic form that can he stored in a computer's memory. The image can then be manipulated.

Bar code scanllers: This type of sc~mner reads bar lines that are printed on prod-lIcts (for example. in a grocery store or departmcnt store). Sec Fi gure 2-1311.

Magnetic scanJlers: These devices read encoded information on the bad: of c redit cards. The magnetic strip on the back of the cards contains the user's encoded account number.

Wireless SCl/Jlllers: A Bluetooth barcode scanner lIses Bluetooth wireless tech-nology to SCllll data. such as from 11 hospital bracelet. and transmit it to 11 com-puter. Sce Figure 2-lJb.

Optical cJwracler recognition (OCR) and optical mark recognitioll (OMR): 111cse devices usc a light source to read characters. marks. and codes: Ihe data is then converted into digital data. Banks usc OCR technology to scan checks. Commonly known as Sc:mtrons, schools and other organizations usc OM R for testing purposes.

I') Ib) FIGURE 2-13 (a) Optica l scanner (b) Bluetooth scanner

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t VOCABULARY scanner




Modl-J8 MODULE 1 Computing Fundamentals

Touch Display Screen The touch display screen, shown in Figure 2-14, is a special screen with pictures or shapes. You li se your fingers to "point" to the desired object to make a selection. You can find theie screens in many public pl.aces sllcn as airports, hotels, banks. libmrics. delivery services, and fast -food restaurants. Many mobile devices have touch screens.

FIGURE 2- 14 Touch screen on a handheld device

Stylus A stylus and digital pen are pen-like writing instruments. See F igure 2-1 5. These devices allow you to input information by writing on II PDA or other mobiLe device or to usc the pen as a pointer.





FIGURE 2- 15 Stylus for mobile device

Environmental Probe:; and Sensors Environmental monitoring in many indus.tries and companie s is a critical component o f stabil ization in the work area. Workers c:m use environmenfal probe.~ and sensor.\ with .a standard \Veb browse r, such as Internet Explorer. to view clements such as the tempcmture and humidity of a remote environment. smoke detector readings. pollution control readings, and so on. Indu stries such as farming, tropical fish pro-duction, moisture monitoring. and warehouse security use environmental probes and

selL~ors .

Remote Controls RemOTe conrrols. also a type of spec ialized inplll device, are used for numerous standard applications, such as television, lights, fan s, and soon. Industry and business also use remote controls for various applications. For example, a construction worker can use a remote comrol to control a crane. or a warehouse worker can have a remote cOlltrol for a product cart.

Security Devices Consider the following scenario: You are going on a two-weck vacation to Tahiti and Bora Bora- you are packed and ready to go. but you do not need a wallet or credit cards. You use your fingerprint as an input device to pay for all of your expe nses.

In infonTI:ltion technology. hiometric .~ is an authcntic:ltion teChnique using automated methods of recognizing a person based on a phys io logical or bebavioral characteristic . Biometric devices consist of a reader or scanning device and software that converts tbe scanned information into a digital format . The scanned information then is compared to a database of stored biometric data.

VOCABULARY biomet ri cs

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MDdl-40 MODULE 1 Computing Fundamentals

Severnl types of biometric identification techniques ex ist. Some of the morc commo n usc a persoll 's fingerprints , facc , handwriting. or voice. Other less common techniq ue .. are retina (analysis of the capillary vessels located at the bac k of the eye), iris (analysis of the colored ring sunuunding the eye's pupil), hand geometry (analysis of the shape of thc hand and length of Ihe fingers). and vei n \an.alysis of pattern of veins 011 the back of the hand and the wrist}.

The process or thc way in which biometric technology works. however. is basically the same for all identification techniques:

Enrollmem: The user enrolls in the system by establishing a baseline measure-ment for comparison.

Sllbmis.~ion: The user presents biological proof of his or her idcll tity to tne c apture systcm.

Verificatioll: Thc system compares tne submitted sample with the stored sample.

Privacy and civil liberties advocates, however, are concerned about the widespread adoption of biomctric systems. They argue that by using biometric data, un authorized parties can access someone's dat~l witnout their conscllI and link it to other information, resulting in secondal)' uses of the information. Tnis erodes tne users' personal control over their private infonnation. On the other hand, biometrics can also be applied to private security. For ex.ample, several companie~ now offer biometric compute r keyboards and USB nash drives with finge rprint authentication that can be used for personal applications. (Flash drives were discussed in Lesson I.) Sec Figure 2-16.

(a) (b)

FIGURE 2- 16 (a) Biometric keyboard scanner (b) Fingerprint scanner

Vi dual Devices Similar to the la.s~r virtual keyboard mentioned earlier, virtual devices usc the syn-chronized positiuning of light-emitting and sensing devices to detect user input. Figure 2-l7a shows a virtual computer keyboard and Figure 2-17b shows a virtual piano keyboard.





(0) (b)

FIGURE 2- 17 (a) Virtual computer keyboard (b) Virtual piano keyboard

Touch-Sensitive Pads llle louch -sensitive pad on a portable device, such as an iPod, enables you to scroll through a list adjust the volume. play music. , 'iew videos or pit:1Ures. and customize settings.

Input Devices for the Physically Challenged A variety o f special input dC\' ices are available for the physically ch'lllenged. Following arc some examples:

Some keyboards can be operated with one hand or with the feet. A progrum called Camera Mouse enables users 10 use a Wcbcam and control the

mouse pointer by moving their heads. A human-computer interface uses eye control to move a pointer and make

selections. A joystick compute r mouse can be operJled with I ~c lip.~. chin. or wilh the

tongue for people with little or [}o head moveme nt. Voice input devices allow visually impaired. blind. and physically challc ngcd

individuals to more easily interact with computers. A compute r di spl ay screen is sensitive to hUlllan toUGh and allows the user to

intcmct with the computer by touching an active area or a targe!. or to control d ata such as pictures or words on Ihe screen.

Specialized Output Devices Simi lar to speci .. l izcd input devices. a varie ty of s pecialized output devices arc .. Iso available:

Pmjec/ors: A data projector projects the computer image onto a screen: this is mostly used for prcscnt .. tions.

Fax machilles {lillI/ax moJems : A fax machine and fax modem tmnsmit and receive document s over a telephone line or through a computer.

Mil iti/ilne/ioll primer. A multifunction printer combines various output options suc h us printjng. scanning. copy in g. and faxin g.

COllI/vi devices/robots: The field of robotics is dclincd as the study, design. lUld lISC of robot systems for m~mufacturing. Some of the typical applic:.t!ions of robots includc tcsti ng. product inspection, painting, assembly, packagi ng. and p




MDdl -42

1-1.1.8


Specialized Printers Impact printers, such as the dot matrix and line printer, have been around for a long time. Dot matrix printers transfer ink to the paper by stri kin g a ribbon with pins. The higher the number of pim. (dpi), the better the resolution or output. The mechanism that actually does the printing is called a printhcad. The speed of the dOl matrix printer is measured in ehamelers per second (cps). With the reduction in cost of laser and ink jet printers, dot matrix printers are used less often toclay. A variation of the dol matrix prin ter is the line printer. This type of high-speed printer is attached primarily to large computers such as m ainfmmes or rnidnmgc servers.

Scycm] other types of specialty pri nters are available. Some examples are:

Thermal: A thermal printer fonns characters by heating paper. The printer requires special hem-sensitive paper.

Mobile: A mobile printer is a small. battery-powered printer. primarily used to print from a note book computer.

Ulbe! {wd poslllge: A label printer prints labels of various types and sizes on an adhesive-type paper: a postage printer is a special type of label pri nter. This lype of printer contains a built-in digit~11 scale and prints postage stamps.

PlotTers/large-f()rmat: Engineers, architects. and graphic artists use plotters and large-fonn at printers for drawings and drafting output.

Output Devices for the Physically Challenged Similar to input devices for the physically challenged . output devices are also available. Following are some eX3Inples:

Screen magnifiers: These devices contain a range of magnifications and a variety of fonts llnd are used to enlarge the information displayed on the com-puter screen.

Screen readers: A screen reader assists people who Me blind or otherwise visll-ally impaired. A speech synthesizer genera lly is used to read the screen content. Some screen readers can also read sca nned documents.

Voice synThesizers: Speech synthesis is the computer-generated simulation of human speech. A voice cha nges written computer text into synthetic speech. This technology is useful especially for people with limited sight.

Connecting Input and Output Devices to the Computer Input and output devices must be connected to the comp uter. Some devices connect to the computer through a physical co nnection. sllch as a port. For instance. you can plug the cable for a physical device into an existing pon located on the back or front of the computer. Some monitors also have ports. Wireless devices Cotlnt!ct through infrared or radio waves.





Ports and Connectors A port, also c;:.lIed a jack, is an interface 10 which a per iphcml device allachcs 10 or communicates with the system unit. Older peripheral device .. usc seri al and parnllcl ports to connect to the computer. Se rial devices transmit data one bit at a lime. lJ:w.!l1e1 devices transfer eight bi ls at a lime. A b it is represented by a 0 Of I . Typically, eight bits make O [)C byte. Most computers traditionally have al Jelisl one pamUci pori and one serial porI. In older compUlers. you willlikcly find a printer connected to 01 parallel port and perhaps a mOllse connected loa scri:ll port. A modem is:1 device Ihal allows one computer to talk to anothe r.

The Ull il,trsai Serial n its (US8) port can connect up [0 127 differenl peripher-als with:1 single cOllnector and supports data trans fe r rates of 1I1) to 200 million bits per second (Mbps) . USB replaces the standard serial and pamllcl ports on newer compute rs. US B 2.0 is a recent and more advanced version of USB technology, with speeds 40 times fll ster than that of its predecessors. Today 's personal computers typi-cally have four to eight USB ports either on the front or back of the system unit. Using a duisy-chain arrangement or a USB bub, you can usc a ~i ngle USB port to connecl up 10 127 peripheral devices. A US B hub is a device Ihm plugs inlo a USB pon und contains multiple USB ports into which cablcs from USB devices elm be plugged . US B also supports plug-and-play and hot plugging. Plllg-lIl1d-play refers 10 Ihe ability of a computer syslem to configure expansion boards .md olher devices automatkillly. Hot plugging is the ability to add and remove devices to a computer while the compu ter IS runnmg and tlave ttle operaung system automatic,llIy recog-niz..: the change.

Another type of external bus is Fire1t'ire. also known as IEEE 1394 and IEEE I 394b. The IEEE 1394 bus standard supports data transfer nltes of up to 400 Mbps and can connect up to 63 extern.al devices: IEEE I 394b pro"idcs speeds up 10 3200 Mbps . ' igu re 2- 18 shows an example of some of the more popular Ir.tditionll l porlS and exa mples of FireWire and US B ports.

FireWire port

USB potts

ports

FIGURE 2-18 Traditiona l, USB, and FireWire ports

VOCABULARY poet

modem

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Uni,e.-sal Serial Bus (USH) plug-and-play .-ireWire

@ EXTRA FOR EXPERTS USB 3.0 has recently been released, and has ten times the current bandwidth of USB 2.0. Transfer ra tes are approximately 4.8 Gb itslsec (Gigabits per sec-ond) and should be a..,ailable in commercial products in 2009.




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VOCABULARY expansion slul


In addition to the preceding ports. you mi ght find three additional special-purpose ports on various computing devices. These special-purpose porls arc:

SCSI: An abbreviation for Small Computer Syslcmlntcrface, SCS I (pronounced skuzzy) is a standard interface for connecti ng peripherals such as disk drives ;:lIld printers.

IrDA: A wireless standard that allows data to be transferred between devices using infmred light instead of cables is called lrDA. Both thc computer and thc device must have an lfDA port, and thc IfDA (XJrt 011 the device must aLign with the lrDA port on the computer.

Bluetoorh: B[uclooth uses radio waves ;:md provides wireless short-range communications of data and voice between both mobile and stationary devices. This technology does not require alignment: it is an alternative to IrDA. See l ' igu re 2- 10

FIGURE 2- 19 Bluetooth device

Erpa".~ioll slots are openings on the motherboard where :.111 expansion board . also called an ad~pter card. elill be inserted. Expansion boards enhance functions of a component of the system unit lmd/or provide connections through a pon or other connectors to peripheral devices. Exp.ansion boards are also called expansion cards, add-ins. and add-ons. See Figu re 2-20.




LESSON 2 Input, Output, and P,oce" ing

Expansion ---Il;" card Expansion slots

FIGURE 2-20 Expansion slots and card

Tr.tdi tionally. rorts have been located on Ihe back of the system unie. With the introduction of portable devices, such as digital camcr.lS and pocket pes, mnny newer computers also indude pOrlS on the front of the sys tem unit. This provides fo r easier :.ccess.

Hardware Installation For most hardw:tre devices to work. they need a set of instruc tions Ihal commu-nic,ltes with thc computer's operating system. This ~ ct of instructions is called u driver. In many instances. the operating system includes drivers for the more popular pe ripheral devices LInd performs tin automatic plug-and-play imnallution fOf newly connected devices.

If thc opcrUling system docs not contain a driver for the hardware, the dri ver needs 10 be inslalled manually. Usually, the software is included wilh the hurdwarc device. If an installation di sk is nOi available, Ihe manuf(lourer"s Web site gcncmll y prGvides a downloadable fil e.

Computer Performance Factors A variety of factors can affect a computer 's pcrfomlance . In Lesson I , you leamed aboUllhe celllmi processor. compuler memory. and inpulfootplll devices. 11lcsc Ih.rce components. plus video capability and disk organization. affetl lhe speed at whjch the computer performs.

The following list provides an overview of these various devices and disc usses how more than one component can slow down or speed up computer performance.

I. Micro/Jroce.ssor: The architecture of the central processor is the most important processing clemen!. CPUs arc classified by generations. The higher the gcner:ltion. the faster and better the processing speed. Some processors support

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1 1.1.9




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FIGURE 2- 21 Computer window


parallel processing. With this type of processing. while one instruction is being executed . the next instruction is fetched from memory and decoded. Thu s. , thc faster the processor, the more instructions per second it can process.

2. Rilllt/Oll! access memol)' (RAM ): The amount of RAM also helps to increase the processing cycle and to enhance the computer 's performance. When the memory capacity is reached , the CP U stores data on the hard drive. This slows down the processi ng cycle because it takes longer for the CPU to read from a hard drive compared to reading from RAM.

3. Hard disk: The size and speed of the hard drive also affects a computer' s performance. The bigger and faster the hard drive. the faster the data is processed. In addition, how the disk is organized affects computer perfonn;mce. If a hard disk contai ns many unneeded and outdated files , it takes longer for the computer to find the information it needs.

4. Video: The video device that is connected to the computer ca.n enhance or slow down the comput er's perfannance. Having adequate video memory far the video card allows the processor to petform 10 its full potential.

Windows Vista provides several options to dctennine what hardware you have in your computer system. In Step-by-Step 2.1 . you learn how to view th is infonnatioll. When you view this information. most likely you will see abbreviations suc h as MB or GB. which are units for measuring bytes. Bits and bytes were discussed in Lesson I.

Step-by-Step 2_1 1. Click the Start button on the taskbar, and t hen click Computer. The

Computer window appears, as shown in Figure 2- 21.

2. Cli c k System praperties on the menu bar. The System screen is displayed (see Figure 2- 22). Most likely, your System screen will display different system information than that in Figure 2- 22.





----.,.....------

_c ___ .. __ ---

-

- 1!lII----

----

System window

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FIGURE 2- 22 System window




MDdl -48 MODULE 1 Computing Fundamentals

5 . Click each of the tabs in the dia log box and read the information con-tained on each tab . If directed by your instructor, use Notepad or your word-processing program and write an overv iew of the features con-tained within the System Properties dia log box.

6. Click the OK button to close the System Properties dialog box, and then close the System window.

ETHICS IN TECHNOLOGY ' ' '''' ~ ~ ~ Computer Viruses The word virus can put fear into anyone who uses the Internet or exchanges disks. How can such a small ..... ord cause such fear? It is because a virus can cause tremendous damage to your computer files!

A virus is a computer program that is wri tten intentionally to attach itself to other programs or disk boot sectors and duplicates itself whenever those programs are executed or the i nfected disks are accessed . A virus can wipe out all of t he files on your computer.

Viruses can sit on your computer for weeks or months and not cause any damage unti l a predetermined date or time code is activated. Not all viruses cause damage. Some are just pranks; maybe your monitor will display some sil ly message. Viruses are created by persons who are impressed with the power they possess because of their expertise in the area of computers; sometimes they create them just for fun . To protect your c:lmputer from virus damage, insta ll an antivirus software program on your computer and keep it running at all times so that it can continuously scan for viruses.

SUMMARY

In this lesson, you Il'arnro:

Input devices enable you to inpul data and commands into the computer. The most C0l111110n input devices arc the keyboard and mouse.

Other type. .. of input devices include the trackball. joystick. wheel. poillling stick. g raphics tablet. tOlleh display screen. stylus, voice recognition dcyices, louchpad, scanner, digital camera. video input. and biometric input.

Monitors and printers arc examples of output devices. Monitors produce soft copy. Primers arc used to produce a paper or hard copy of the processed result.

Criteria for selecting a printer include speed. print quality. and cos!.

[nput and output dcvices must be connected to the computer. Somc input and output devices communicate with the com puter through a physical mnnectioll. Wireless devices commu-nicate with the computer through infrared or radio waves.

Peripheral devices arc connected 10 [he computer through serial, parallel. and Universal Serial Bus (USB) pGm. USB is a newer standard expected 10 replace serial and parallel ports.

Firc\Vire is a type of external bus thm can amncet up to 63 external dc:vices.

SCSI. IrDA, and Bluelootll arc s.pecial-purpos.e ports. A computers pc:rformance is affected by the speed of the pro

cessor, the amount of RAM, hard disk size and sp'~ed , capabil. ity of monitor. and disk organization.





VOCABULARY REVIEW Detin~ th e- following t('rms: audio inplII biometrics d ig ital camcra cxpansion slot FireWirc inkjct printer input

keyboard laser prinler modcm monitor mouse

output plug -and-play

REVIEW QUESTIONS TRUEI FALSE Cirde T if the statement is true- or F irthe state-ment is false_

1. Vidco input is thc proccss of capturing full -motion images with a vidco camcra.

2. Input and outpul device~ perfonn the sallie funelion.

pointing device port printer scanner

trackball Universal Scrial Bus (USB)

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T F T F T F 3. A data projector is a type of specializcd output device that projects the computer image onto a screen. u~ually duri llg a

presentation.

T F

T F 4. Input and output deviccs can stand alone-they do not nced to be connected to the computer.

5. An optical mousc uscs a laser to detcct!.hc mouse's movcment.

MULTIPLE CHOICE Select the best response for the following statements.

I. Wh ich of the fol lowing is 110/ considered an input device?

C. mouse

B. scanner D. monitor

2. \hich onc of the follow ing is a type of scanner that con"erL~ graphics into an eleetronic form? A. image scanner C. bar code scanner

B. magnetic scanner D. OCR scanner

3. Plug-and-play refers to a computer's abili ty to _______ _

A. connect mu ltiple USB devices

B. c()nfi gure hordwnrt: devices uutolllu tically C. c()t1Imunicatc with lhc system unit D. talk to another computer

4. produce an image by manipulating light within a layer of liquid crystal cells.

A. Gas plasma monitors C. CRT monitors

B. LCD panels D. Scanners

5. \hich of thc following is a biometric identification scunning technjque? A. fingerprint C. V01ee

B. face D. all of the above




Modi -50 MODULE 1 Computing Fundamentals

FILL IN THE BLANK Complete the following senll'nces by wrilin g the cor~ct word or words in the blanks provided.

I. A(n) ________ i ~ the most widely used device for entering data into the computer.

2. ________ is data or instructions entered into the computer.

3. The ________ port can conneCI up to 127 different peripherals with a single connector.

4. To improve perform ance dramatically. increase the amount of ________ on your COllllJutcr.

S. A(n) ________ is a small. battery-powered printer. primarily used to print from a notebook computer .

PROJECTS PROJECT 2- 1 Gmai! is a frcc Web mail service provided through Googlc. Complete the following sleps to create an account.

I. Opcn your browser and go to IlIIp:llmllil.google.comlllwifl heip/open./wlll.

2. W hen the Welcome to Gmu;] screen is displayed, read the information prov ided on the page. TI1Cil cl ick thc Create an accounl link.

3. Type your first and las t name and desired 10Bin name. C lick the check availability button to verify that thc name is availablc.

4. When selceting a password, Google assists w ith a password strength level- poor, fai r, and strong. Your goal is \0 create a strong password. It must be a minimum of eight character.;.. Be sure to wri te down your password or send the password to yourself in an e-mail.

S. If you arc using a schoo! computer or a computer other than your own. do not se!eet lhe " Remember me on Ihis computer" or the "Enable Web History" check boxes.

6. Select a Security Question that you arc sure to remember. E-maillhe answer 10 yourself.

7. If you have another e-mai! address. you can emer it illlo thc Secondary c-mai! text box. However, this is nOl necessary or required.

8. For Word Vcrifkation. type the charactcrs displayed on the form.

9. Read the Terms of Service. and then click the I accept. C reate my account bullon.

10. When an Introduction to Gmail page is displayed, read the information on the page and then click Sho w me my account. Sign in to your account using your user name and password.

II. Click the Compost' Mail link and send a message to your instructor and/or another classmate. List three facts in the message thal rdate to the topics presented in this lesson. Print a copy of your message and submit it to your illslructor.

f'Or additional infonnation, sce hltp:/Illwil.goog le.com/supporlf.

PROJECT 2- 2 Biometric technology is lhe autom[lted method of recognizing a person based on a physiological or behavioral characteristic. Usc lhe Internet and other sources to research this topic.

I. Use your favorite search engine to search for Web pages discuss ing b iometric technology.

2. Ba~ed on your findings, creale a d(K;ument listing the pros and cons of biometric technology. Include your personal opin ion about this topic.

3. Submit the document to your instructor as rcquested.

PROJECT 2- 3 Preparc a wriltcn report on input devices.

I . Select at least fivc input dcviccs discussed in Ihis lesson.

2. Create a document for the report. Include a table i[1 your report listing each input device. describing how it could be used. and explaining the dcvice's advantages and disadvantages.

3. Submit the document to your instruclOr as rcquested.

I:lI TEAMWORK PROJECT This exercise is a student role-playing activity. Students arc given a specific task and a set of rules. They then role-play paris of a computer to accomplish thc task. Studcnt roles include a processor, main memory. 5torage dcvice.~. ilnd input/outpul devic(;~. Following are some of the task examples: (a) inpulling pictures from a digi-tal camcra, modifying and viewing the !JictUICS . and outpUll ing and printing the pictures; (b) using word-proccssing software toereate a report on a specified schoo! lopic. addi ng pictures \0 the repol1. and then priming copies for all students in the class; (c) students usc a 5prcadshcct program to create a worksheet and chart and then print copies for al! students in the class: Cd) students use a presentation program such as PowerPoilit and create a prescntation with tex!. images. and video: they display the prcscntation to the class.





CRITICAL THINKING You wan! to leam more about how the computer processes data and the factors that innucncc the processing speed. Your ins tructor thinks this is a great idea and asks you to prepare a report on what

ONLINE DISCOVERY Google has a feature thai focuses solely on blog searching. This fea-turc. called Blog Search. is located at www.google.comlblogsearch.

Modl-51

factors produce the Dcsl overall processing system. Prepare !I report lis ting the devices you would sekct to produce the best all -around processing system .

Access this Web site and then search for increase COmpl/fer speed. Wri te a one-page report on what you learned.

Documents

Input, Out and Processing