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Lesson 2Input, Output and Processing

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Standard Input Devices

Input – must be entered into computer and stored temporarily

or permanently.

Modem – device that allows one computer to talk to another.

Keyboards – Most common input device for entering text and numbers. Various types:• Ergonomic – use of more natural/comfortable hand, wrist and arm

positions• Cordless/Wireless – battery-powered transmit via wireless• Specialized – special keys represent specific items

(example: fast-food restaurants)• Security – biometric fingerprint reader, magnetic stripe or smart card

reader• Foldable/Flexible – used with mobile devices; soft touch and water

resistant. NIK-Nearly Indestructible Keyboard• Laser Virtual – packaged small; use laser to project full-size keyboard.

Connects to any PC or Smartphone

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Standard Input Devices

ENHANCED KEYBOARD

BIOMETRIC KEYBOARD

FLEXIBLE AND

FOLDABLE KEYBOARDS

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Standard Input Devices

VIRTUALKEYBOARD

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Standard Input Devices

Pointing Devices – Input device to position pointer on screen; has several shapes usually an arrow; use to move device; select objects like text or graphics; click icons, buttons, or links• Mouse – Most common pointing device for the PC; fits in palm of hand. Various

types:• Mechanical – ball located in bottom of mouse; rolls on flat surface; sensors detect

movement (direction and distance)

• Optomechanical – same as above but uses optical sensors to detect movement• Optical – uses laser to detect movement; have no mechanical moving parts;

respond more quickly and precisely than mechanical or optomechanical mice• Wireless – battery powered; infrared waves to communicate with computer• Trackball Mouse – upside down mechanical mouse with ball on top• Radio Frequency – typically wireless, but uses radio frequency instead of

infrared waves• Foldable – wireless and flexible to be easily folded or rolled up

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Standard Input Devices

OPTICAL

RADIO FREQUENCY FOLDABLE

TRACKBALL

WIRELESS

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Standard Input Devices

Pointing Devices – continued• Mouse – continued• Mice have two or three buttons and a wheel• Left click = mouse operations• Right click = shortcut menu• Point and Click triggers action in computer• Pointing – places pointer in designated location• Clicking – pressing and releasing mouse button to select specific location in doc• Dragging – pressing mouse button and moving mouse = highlighting text• Double-Clicking – press and release mouse button rapidly twice = select a word• Triple-Clicking – press and release mouse button rapidly three times = select a

paragraph• Right-Clicking – displays a shortcut menu• Rotating – rolling wheel forward or backwards = scroll vertically up or down• Tilting – pressing wheel left or right = scroll horizontally

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Standard Input Devices

Pointing Devices – continued• Trackball – upside down mouse; use thumb and/or fingers to

control ball motion; mouse is stationary; good choice for limited desk space; some keyboards have built-in trackballs

• Touchpad – common feature on laptop/notebook computers; specialized surface to convert motion and position of finger to placement on the computer screen.

• Pointing Stick – pressure sensitive device looks like an eraser; usually contained on notebook computer between the G, H, and B keys; use forefinger to move

• Audio Input – sound entered into computer; examples: microphones, CD/DVD players, radios, electronic keyboards; use voice recognition to speak commands into computer or enter text; computer has to have voice recognition software

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Standard Input Devices

TRACKBALLMOUSE KEYBOARD

WITH TRACKBALL

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Standard Input Devices

POINTING STICK

TOUCHPAD

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Standard Output Devices

Output – data processed into useful format; display information (examples: printed text, spoken words, music, pictures, videos, and graphics; most common are monitors and printers.

Monitors – visual display device; comprised of screen, housing, electrical components; display is called a soft copy since it is temporary. Various types:• CRT – Cathode Ray Tube; earliest type, monochrome or color; heavy;

nearly obsolete; replaced by flat panel monitors• Flat Panel – take up less space; lighter; larger viewing area• LCD – Liquid Crystal Display; produces image by manipulating light

within the Liquid Crystal cells; originally for notebooks; 1997 started producing full-size monitors as alternative to the older CRTs; older LCD produced square display; newer monitors = widescreen format

• Plasma – Gas plasma technology; tiny amount of gas charged by electricity; illuminates miniature colored fluorescent lights; typically widescreen format

12Standard Output Devices

CRT MONITOR LCD MONITOR GAS PLASMA MONITOR

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Standard Output Devices

Output Devices – Continued• Printers – produce paper copy (hard copy); hard copy =

permanent; several types available with differences to consider:• Speed – measures in ppm (pages per minute); varies

according to text and graphics• Print Quality – measured in dpi (dots per inch); higher dpi =

better resolution or print quality.• Price – original cost of printer and what it cost to maintain

it; price range from inexpensive to thousands of dollars; ink and toner cartridges need to be replaced periodically and have wide range of pricing as well

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Standard Output Devices

Output Devices – Continued• Printers – Continued• Classifications• Impact – use a mechanism to strike paper to form letters or

graphics• DOT Matrix example of this type.

• Non-Impact – form characters without striking paper• Laser and Inkjet examples of this type• Laser – produces images like a copy machine; image made from

toner, high quality output; generally affordable but can be expensive

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Standard Output Devices

HOW A LASER

PRINTER WORKS

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Standard Output Devices

HOW AN INKJET

PRINTER WORKS

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Standard Output Devices

Output Devices – Continued• Speakers – generate sound (examples: music or

instructions); headphones/earbuds = private

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Specialized Input Devices

Other types of input devices that are used for specialized applications.• Digital Cameras – store pictures digitally and transferred to

computer’s memory. Various storage media:• Flash Memory Cards, Memory Sticks, USB Keys, Mini Discs, SD

Cards• Video input is a set of full motion images captured with video camera.• DV camera records video as digital signals. They can capture still

images as well.• PC Video camera sends live images via the web, video telephone

calls, or e-mail• Mini digital small enough to fit in pocket.• Webcams = video capturing cameras connected to computers or

computer networks. Display images via the web

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Specialized Input Devices

MINIATURIZED DIGITAL VIDEO

CAMERA

WEARABLE VIDEO CAMERA

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Specialized Input Devices

• Game Controllers – Joystick and Wheel are types of pointing devices; used primarily for games

JOYSTICK

STEERING WHEEL

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Specialized Input Devices

• Scanners – Devices used to change images into computer code; various sizes and types:• Image – converts image to electronic form to store in computer

memory; manipulate images• Bar Code – reads bar lines printed on products• Magnetic – read encoded information on credit cards; contains

user’s encoded account information• Wireless – use Bluetooth technology to scan barcode data and

transmit to computer• Optical Character Recognition (OCR)

Optical Mark Recognition (OMR) – use light source to read characters, marks, and codes; data converted into digital format; example: Banks use OCR to scan checks; Schools use OMR for testing (Scantron forms)

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Specialized Input Devices

OPTICAL SCANNER BLUETOOTH

SCANNER

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Specialized Input Devices

• Touch Display Screen – special screen that reacts to direct touches within display area; use finger or hand; can be found in places like: airports, hotels, libraries, delivery services, fast-food restaurants; mobile device like iPhone, iPad, notebook computers have touch screens

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Specialized Input Devices

• Stylus – Pen-like writing instrument used to enter information by writing or pointing on a screen.

• Environmental Probes/Sensors – used to view information like humidity and temperature in remote areas; smoke detector or pollution control readings; industries fish farms, moisture monitoring, warehouse security

• Remote Controls – manage devices like TVs, lights, fans, factory equipment (cranes, carts, etc.)

STYLUS

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• Security Devices – Biometrics to authenticate to recognize a person based on a physiological or behavioral characteristic; uses reader/scanner and software to convert scanned information into digital format; used to identify people based on fingerprints, face, voice, or hand; analysis of retina, iris, hand geometry, or vein are other options; how it works:

• Enrollment – establishes baseline measurement for comparison

• Submission – present biological proof of identity to capture machine

• Verification – compares submitted sample to stored sample

• Uses in computer industry• Computer Keyboards and USB Flash Drive with

fingerprint authentication

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Specialized Input Devices

• Virtual Devices – Similar to Laser Keyboard; use synchronized position of light-emitting and sensing devices to detect user input

• Touch-Sensitive Pads – Like the touchpad of a notebook; used by device like iPod, iPad, etc.; use to scroll through lists, adjust volume, view pictures or videos, or customize settings

• Input Devices For the Physically Challenged – • Keyboards operated with one hand or foot• Camera Mouse allow users to use Webcam and control mouse

pointer with their head• Human-Computer interface uses eye control to move pointer• Joystick mouse can be operated by lips, chin, or tongue• Voice input allows those that are visually or physically impaired to

interact with computers

27Specialized Output Devices

• Projectors – project images onto a screen for presentation• FAX Machines – transmit and receives documents via

telephone line or through computer• Multi-function printer – combines functions like printing,

copying, scanning, faxing• Control devices/robots – Robotics is the study, design,

and use of robot systems in manufacturing; applications for testing, product inspection, assembly, packaging, and painting

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Specialized Output Devices

• Specialized Printers Examples:• Dot matrix – uses printhead to strike paper to form character or

number; measured in (CPS) characters per second; seldom used anymore

• Line – variation of the Dot matrix; connected to large mainframe computers or servers

• Thermal – forms characters by heating paper; requires special paper

• Mobile – small, battery-powered; for use with notebook computers

• Label and Postage – used to print labels with adhesive on one side; postage printer contains scales and prints postage stamps

• Plotters/large format – used by engineers, architects, or graphic artists; produces large drawings or drafting plans

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Specialized Output Devices

• Output Devices For the Physically Challenged – • Screen Magnifiers – Range

of magnification and fonts that enlarge information on screen

• Screen Readers – assists those visually impaired by reading screen content; can read scanned documents

• Voice Synthesizers – changes computer text into synthetic speech

SCREEN MAGNIFIER

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Ports and Connectors

• Ports – interface which a peripheral device attaches to or communicates with the computer or other peripheral device• USB (Universal Serial Bus) – connects up to 127

peripheral device with single connector; transfer rate = 200 million bits per second; USB 3.0 latest version; replaced standard serial and parallel ports of older computers; typically 4-8 connectors located on computer

• Plug and Play – computer system can configure expansion boards automatically; “Hot Plugging” = add/remove devices will computer is running

• Firewire – known as IEEE 1394 (data transfer up to 400 Mbps) or IEEE 1394b (data transfer up to 3200 Mbps); connects up to 63 devices USB

FIREWIRE

31Ports and Connectors

• SCSI (Small Computer System Interface) – pronounced “SKUZZY”; standard interface for connecting peripherals like disk drives and printers

• IrDA – wireless standard that allows data to be transferred between devices using infrared light instead of cables; both devices must have IrDA port

• Bluetooth – uses radio waves to provide wireless short-range communication between mobile and stationary device; alternative to IrDA

• Expansion slots – openings on motherboard to put expansion boards/cards to enhance functions of a component or provide a connection; expansion boards also called:• Adapter Cards• Expansion Cards• Add-ins• Add-ons

• Hardware Installation – needs set of instructions to communicate with computer; instructions are called drivers; installed automatically or manually

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Considering Computer Performance Factors

• Microprocessor – most important element; higher the generation = faster and better processing speed and more instructions per second can be processed

• RAM (Random Access Memory) – amount of RAM helps to speed up processing cycle; more memory = better performance from computer; computer reads from RAM faster than the hard drive

• Hard Disk – size and speed affects computer performance; bigger and faster = faster data processing; disk organization affects computer performance therefore remove unneeded or outdated files

• Video – can enhance or slow computer performance; have adequate video memory to optimize performance

33QUICK QUIZZES

1) A(n) __________ is a device that allows one computer to talk to another.

Answer: Modem

2) The __________ is the most commonly used input device for entering text and numbers into a computer.

Answer: Keyboard

3) Desktop computers typically use a(n) __________ as their display device.

Answer: Monitor

34QUICK QUIZZES

4) What is output?

Answer: Output is data processed into a useful format

5) __________ are devices that can change images into codes for input to the computer.

Answer: Scanners

6) What is biometrics?

Answer: An authentication technique using automated methods of recognizing a person based on a physiological or behavioral characteristic.

35QUICK QUIZZES

7) A(n) __________ printer is a small, battery-powered printer, primarily used to print from a notebook computer.

Answer: Mobile

8) The field of __________ is defined as the study, design, and use of robot systems for manufacturing.

Answer: Robotics

9) A(n) __________ is an interface to which a peripheral device attaches to or communicates with the system unit or other peripheral devices.

Answer: Port

36QUICK QUIZZES

10) What is plug and play?

Answer: This refers to the ability of a computer system to configure expansion boards and other devices automatically.

11) True or False? The higher the CPU generation, the faster and better the processing speed.

Answer: True

12) True or False? To improve computer performance dramatically, increase the amount of RAM on your computer.

Answer: True