© 2013 by the McGraw-Hill Companies, Inc. All rights reserved. Chapter 2A Input Devices.

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Chapter 2AChapter 2A

Input DevicesInput Devices

22

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Learning ObjectivesLearning Objectives

2.12.1 Compare how to interact with an operating Compare how to interact with an operating system using a graphical user interface and a system using a graphical user interface and a command-line interfacecommand-line interface

2.22.2 Summarize how to input information into a Summarize how to input information into a computer with a computer’s keyboard, mouse, computer with a computer’s keyboard, mouse, and touch screenand touch screen

2.32.3 Describe other ways to input information into a Describe other ways to input information into a computercomputer

2.42.4 Explain why and how computer users need to Explain why and how computer users need to address the ergonomics of using a computeraddress the ergonomics of using a computer

33

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

User InterfacesUser Interfaces• Operating system basicsOperating system basics• Graphical user interfacesGraphical user interfaces• Command-line interfacesCommand-line interfaces

44

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Operating System BasicsOperating System Basics• An An operating systemoperating system controls the system’s hardware controls the system’s hardware

and interacts with the user and application softwareand interacts with the user and application software• It performs the following functions: It performs the following functions:

– Displays the on-screen elements with which you interact—Displays the on-screen elements with which you interact—the the user interfaceuser interface

– Loads programsLoads programs– Coordinates how programs work with the computer’s Coordinates how programs work with the computer’s

hardware and other softwarehardware and other software– Manages information storage and retrievalManages information storage and retrieval

55

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Graphical User InterfaceGraphical User Interface• Graphical user interface (GUI)Graphical user interface (GUI): Users launch : Users launch

programs and make choices with graphical objectsprograms and make choices with graphical objects– ShortcutsShortcuts - small pictures on the desktop which represent - small pictures on the desktop which represent

links to resources links to resources – IconsIcons - pictures used to represent an object - pictures used to represent an object

• Elements on the Windows desktop:Elements on the Windows desktop:– TaskbarTaskbar – Start buttonStart button – Start menuStart menu– Quick Launch barQuick Launch bar

66

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Graphical User InterfaceGraphical User Interface• When you right-click an object in Windows, a small menu When you right-click an object in Windows, a small menu

usually appears called a usually appears called a shortcut menu shortcut menu or a or a context menucontext menu• The window currently in use is the The window currently in use is the active windowactive window• Dialog boxes Dialog boxes are windows that appear when the OS or are windows that appear when the OS or

application needs to give you status information application needs to give you status information • Common GUI features of a windowCommon GUI features of a window

– Title barTitle bar– Menu barMenu bar– ToolbarsToolbars– Scroll barsScroll bars

77

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Command-line InterfaceCommand-line Interface• The user enters typewritten commands rather than The user enters typewritten commands rather than

interacting with graphical objects to execute tasksinteracting with graphical objects to execute tasks• Users enter commands at a Users enter commands at a promptprompt on the screenon the screen

– For example: in DOS, the prompt usually includes the For example: in DOS, the prompt usually includes the identification for the active disk drive (a letter followed by identification for the active disk drive (a letter followed by a colon), a backslash (\), and a greater-than symbol (>), as a colon), a backslash (\), and a greater-than symbol (>), as in in C:\>C:\>

88

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Common Input DevicesCommon Input Devices• Input devices enable users to enter information and Input devices enable users to enter information and

commandscommands• PortsPorts - connect input and output devices to the - connect input and output devices to the

computer. computer. – Many devices connect via Many devices connect via USB portsUSB ports

• Common input devices include: Common input devices include: – KeyboardKeyboard– MouseMouse– TrackballsTrackballs– Touchpads and pointing sticksTouchpads and pointing sticks– Touch screensTouch screens

99

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

KeyboardKeyboard• The primary input device for entering text and The primary input device for entering text and

numbersnumbers– Alphanumeric keysAlphanumeric keys - Letters, numbers, the space bar, and - Letters, numbers, the space bar, and

the Tab, CapsLock, Backspace, and Enter keysthe Tab, CapsLock, Backspace, and Enter keys– Modifier keys Modifier keys - Alt (Alternate), and Ctrl (Control)- Alt (Alternate), and Ctrl (Control)– Numeric keypadNumeric keypad - A set of numbers, operation signs, and - A set of numbers, operation signs, and

cursor movement keyscursor movement keys– Function keysFunction keys—Keys labeled F1, F2, etc.—Keys labeled F1, F2, etc.– Cursor-movement keysCursor-movement keys—Navigate the cursor around the —Navigate the cursor around the

screenscreen

1010

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Mouse and TrackballMouse and Trackball• Mouse - a Mouse - a pointing device pointing device that is widely used for that is widely used for

entering data on a full-sized PC entering data on a full-sized PC • The The pointerpointer allows users to select the specific allows users to select the specific

graphical objects they wish to activate or changegraphical objects they wish to activate or change• A mouse may be: A mouse may be:

– mechanicalmechanical - sensors read information from a rolling ball - sensors read information from a rolling ball– optical optical - a sensor and image processor reads and interpret - a sensor and image processor reads and interpret

information from a beam of lightinformation from a beam of light• TrackballTrackball – a pointing device in which you move the – a pointing device in which you move the

pointer by rolling a ballpointer by rolling a ball

1111

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Using the MouseUsing the Mouse• PointingPointing is moving the pointer to a location on the screenis moving the pointer to a location on the screen• To To clickclick, press and release the button on the mouse, press and release the button on the mouse

– Double-clicking - Double-clicking - pressing the primary mouse button twicepressing the primary mouse button twice– Right-clickingRight-clicking - - pressing and releasing the non-primary pressing and releasing the non-primary

buttonbutton• DraggingDragging - pressing and holding the mouse button and - pressing and holding the mouse button and

continuing to hold it as you move the mousecontinuing to hold it as you move the mouse• ScrollingScrolling is moving a list of information up or down on the is moving a list of information up or down on the

screenscreen

1212

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Touchpads and Pointing SticksTouchpads and Pointing Sticks• TouchpadTouchpad (or (or trackpadtrackpad) – a pointing device operated ) – a pointing device operated

by moving a finger across a small touch-sensitive by moving a finger across a small touch-sensitive surfacesurface

• A pointing stick is usually A pointing stick is usually positioned near the positioned near the middle of a portable middle of a portable computer’s keyboardcomputer’s keyboard– Generic terms include Generic terms include

integrated pointing integrated pointing devicedevice and and 3-D point stick3-D point stick

1313

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Touch ScreensTouch Screens• Accept input from a user’s Accept input from a user’s

fingertips directly on the fingertips directly on the computer screencomputer screen

• Computers and terminals Computers and terminals with a single purpose use with a single purpose use touch screens offering a touch screens offering a menu of choicesmenu of choices

• Smart phones and tablet Smart phones and tablet PCs have more PCs have more sophisticated touch sophisticated touch screensscreens

1414

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Inputting Data in Other WaysInputting Data in Other Ways

• Devices for the handDevices for the hand• Optical input devicesOptical input devices• Audio input devicesAudio input devices• Inputting musicInputting music• Video input devicesVideo input devices• Digital camerasDigital cameras

1515

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Devices for the HandDevices for the Hand• Pens are used for tablet PCs, PDAs, and other Pens are used for tablet PCs, PDAs, and other

handheld computershandheld computers• Game controllersGame controllers - input devices designed for a - input devices designed for a

particular set of gamesparticular set of games– Game padsGame pads - small, flat devices designed to be held with - small, flat devices designed to be held with

both handsboth hands

1616

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Optical Input DevicesOptical Input Devices• Use light as a source of inputUse light as a source of input• Bar code readersBar code readers are scanners that read are scanners that read bar codesbar codes

– QR CodesQR Codes are a new format for storing data visuallyare a new format for storing data visually• Image scannersImage scanners convert any printed image into convert any printed image into

electronic formelectronic form– Text documents can be scanned with Text documents can be scanned with optical character optical character

recognition (OCR) softwarerecognition (OCR) software to translate the image into to translate the image into texttext

• Biometric scanners Biometric scanners analyze physical patterns in analyze physical patterns in humanshumans

1717

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Audio and Visual Input DevicesAudio and Visual Input Devices• Audio Input Devices:Audio Input Devices:

– Microphones are used to record speechMicrophones are used to record speech– SpeechSpeech recognitionrecognition or or voicevoice recognitionrecognition software software

translates spoken words into texttranslates spoken words into text

• Video Input Devices:Video Input Devices:– PC video camerasPC video cameras capture capture

full-motion video imagesfull-motion video images– A A video capture cardvideo capture card lets lets

the user connect other the user connect other video devices to the PCvideo devices to the PC

1818

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Inputting MusicInputting Music• Import files from CDs, MP3 Import files from CDs, MP3

players or tape playersplayers or tape players• A built-in musical A built-in musical

instrument digital interface instrument digital interface (MIDI) port or MIDI adapter (MIDI) port or MIDI adapter allows the connection of allows the connection of electronic instruments to electronic instruments to your computeryour computer

1919

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Digital CamerasDigital Cameras• Digital camerasDigital cameras - portable, handheld devices that - portable, handheld devices that

electronically capture still imageselectronically capture still images• The images may be copied to a PC, where they may The images may be copied to a PC, where they may

be edited, copied, printed, etc. be edited, copied, printed, etc. • Most digital cameras can store dozens to hundreds Most digital cameras can store dozens to hundreds

of high-resolution imagesof high-resolution images

2020

© 2013 by the McGraw-Hill Companies, Inc. All rights reserved.

Ergonomics and Input DevicesErgonomics and Input Devices• ErgonomicsErgonomics is the study of is the study of

the physical relationship the physical relationship between people and their between people and their toolstools

• Repetitive stress injuries Repetitive stress injuries (RSIs)(RSIs) occur when repetitive, occur when repetitive, improper use of a muscle improper use of a muscle group leads to strain injuriesgroup leads to strain injuries– Carpal tunnel syndromeCarpal tunnel syndrome - a - a

wrist or hand injury caused by wrist or hand injury caused by using a keyboard for long using a keyboard for long stretchesstretches