Fundamentals of

Computers

Slide 1

Input

Input is any data entered into the computer’s memory.

Types of input include:Data – Unorganized information (words, numbers, images, or sounds) that the computer converts to meaningful information

1.Software – Programs transferred from storage devices to the computer’s memoryCommands – Instructions that tell the computer what to doResponses – Prompts requiring user feedback

Slide 3

Input Devices: Giving Commands

Keyboard

Mouse

Other Pointing Devices

Slide 10

Audio Input

Computers can accept input from a microphone.An expansion card called a sound card records and

plays back sound files. Sound files contain digitized sound data.Popular sound file formats include:

Windows WAVMoving Pictures Expert Group (MPEG)MP2 and MP3Musical Instrument Digital Interface (MIDI)

Slide 11

Audio Input: Speech Recognition

Speech recognition is a type of input in which the computer recognizes words spoken into a microphone.

Special software and a microphone are required.

Latest technology uses continuous speech recognition where the user does not have to pause between words.

Slide 12

Digital Cameras Digital Video

Click on the picture to play the video.

Digital Input: Digital Cameras and Digital Video

Slide 13

ScannersFlatbed

Fax Machines

Alternative Input Devices

Barcode reader

Slide 16

Output Devices: Engaging our Senses

Output devices are peripheral devices that enable us to view or hear the computer’s processed data. Visual output – Text, graphics, and video

Audio output – Sounds, music, and synthesized speech

Slide 17

Monitors

A monitor is a peripheral device which displays computer output on a screen.

Screen output is referred to as soft copy.

Types of monitors: Cathode-ray tube (CRT)

Liquid Crystal Display (LCD or flat-panel)

CRT LCD

Slide 20

Monitor Specifications

Screen size – The diagonal measurement of the screen surface in inches (15, 17, 19, 21)

Resolution – The sharpness of the image determined by the number of horizontal and vertical dots (pixels) that the screen can display (800 x 600, 1024 x 768, 1600 x 1200)

Refresh rate – The speed at which the screen is redrawn (refreshed) and measured in Hertz (Hz) (60Hz, 75Hz)

Slide 21

Printers

A printer is a peripheral device that produces a physical copy or hard copy of the computer’s output.

Slide 22

Inkjet Laser

Types of Printers

Inkjet printer, also called a bubble-jet, makes characters by inserting dots of ink onto paper

Letter-quality printouts Cost of printer is inexpensive

but ink is costly

Laser printer works like a copier

Quality determined by dots per inch (dpi) produced

Color printers available Expensive initial costs but

cheaper to operate per page

Slide 23

Plotter

A plotter is a printer that uses a pen that moves over a large revolving sheet of paper.

It is used in engineering, drafting, map making, and seismology.

Slide 24

WMA MIDI MP3 WAV

Beethoven 1:15 min

Rocky 2:56 min

Hornsby 48 sec

Cheers 15 sec

Click an icon to play music.

Click the icon again to stop playing.

Try clicking on Cheers while playing music.

Audio Output: Sound Cards and Speakers

Audio output is the ability of the computer to output sound.

Two components are needed:

Sound card – Plays contents of digitized recordings

Speakers – Attach to sound card