lecture notes2-3 - Te Technology in Action Chapter 2...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Te Technology in Action Chapter 2 Looking at Computers: Understanding the Parts 1 Chapter Topics • • • • • • • Functions of a computer Data versus information Bits and bytes Input devices Output devices System unit Ergonomics 2 Computers Are Data Processing Devices • Computer’s four major functions: – Gathers data (users input data) – Processes data into information – Outputs data or information data or information – Stores data and information 3 Data Data vs. Information • Data: Representation of a fact or idea • Information: Organized, meaningful data 4 Bits and Bytes: The Language of Computers • Bit – Binary digit – 0 or 1 • Byte – Eight bits bits • Each letter, number, and character = a string of eight 0s and 1s 5 How Much Is a Byte? 6 Computer Computer Software • Software: Programs that enable hardware to perform different tasks – Application software – System software software 7 Computer Hardware 8 Input Devices • Devices used to enter information or instructions into the computer – Keyboard – Mouse/ pointing device device – Microphone – Scanner – Digital camera – Stylus 9 Keyboards Keyboards • The QWERTY layout is standard on most PCs • Enhanced keyboard features include number, function, and navigation keys. 10 Dvorak Keyboards • Puts the most commonly used keys on “home keys” • Reduces distance of finger stretches 11 Specialty Keyboards • • • • Notebook keyboard PDA stylus Tablet PCs Wireless keyboard 12 Mice Mice • Optical mouse – Needs no mouse pad – Doesn’t need cleaning – Is more expensive • Trackball – Easier on wrists – Stays stationary on desk • Wireless – Use radio or light waves 13 New Mouse Features • Instant viewer • Magnifier • Customizable buttons buttons • Web search 14 Other Input Devices • Scanners – Text – Images • Digital cameras Flatbed scanner Handheld scanner – Images – Video Digital camera Camcorder 15 Other Other Input Devices • EPOS Digital Pen • Web Cam – Live video 16 Inputting Sound • Microphones used for: – Podcasts – VideoVideoconferencing – Internet phone calls – Speech recognition 17 Input Input Devices for the Physically Challenged • Visual impairments – Voice recognition – Keyboards with large keys – On-screen keyboards keyboards • Motor control issues – Special trackballs – Head-mounted devices Head- 18 Output Output Devices • Send processed data out of the computer – Monitors – Printers • Output devices make: – Soft copies (video, sounds, control signals) – Hard copies (print) 19 Monitor Types • CRT Cathode Ray Tube • LCD Liquid Crystal Display Cathode Liquid – – – – – Less expensive Use much more space Use more energy Offer better viewing angles Legacy technology – – – – More expensive Use far less space More energy efficient Less viewable from an angle 20 Key Monitor Features • Screens are grids made up of millions of pixels. • LCDs: Liquid crystal is sandwiched between two transparent layers to form images • CRTs: Pixels illuminated by electron beam that CRTs: Pixels illuminated by electron beam that passes passes back and forth across screen 21 LCD LCD Quality Factors • Resolution • Passive vs. active matrix display • Viewing angle • Contrast ratio ratio • Brightness • Response time 22 LCD versus CRT • LCD monitors: – take up less space – are generally brighter – cause less eyestrain – use less energy – weigh less • CRT monitors: – used to offer more resolutions – used to produce better color and clarity 23 Other Video Output • Touch-screen monitors Touch– Double as both input and output devices • Data projectors – Project a computer image to a large screen for sharing with large groups 24 Printers Printers • Impact printers – Dot-matrix Dot- • Nonimpact printers – Inkjet – Laser • Specialty printers – Multifunction – Plotters – Thermal printers 25 Nonimpact Printers • Inkjet – Less expensive device – Print high-quality color images cost effectively • Laser – More expensive device – Faster printing speed – Less expensive per page in B&W – Color lasers are becoming less expensive 26 Choosing a Printer • • • • • • Speed (ppm) Resolution (dpi) Color output Memory Use and cost Cost of consumables 27 Outputting Outputting Sound • Speakers and headphones 28 The System Unit • Box that contains the central electronic components of the computer: : – CPU/RAM/ motherboard – Expansion cards – Power supply – Storage devices 29 The Front Panel • Power control • Drive bays • Memory card reader reader • Productivity ports 30 Power Power Controls • Power-on button: Turns on system, should not be used to turn it off • Other options: – Sleep mode – Hibernation – Warm boot 31 Drive Bays • Internal drive bays: – Cannot be access from outside the system – Reserved for internal hard drives • External drive bays: – Can be accessed from outside the system – CD or DVD drives – Floppy and Zip drives 32 Hard Disk Drive • Permanent (nonvolatile) storage • Internal or external versions 33 Flash Flash Drives/Flash Memory • Flash drives (jump drives) – Newer storage alternative – Plug into USB ports • Flash memory cards – Slide into slots in the system 34 Storage Media Capabilities 35 On the Back • Ports for peripherals • Types of ports: – Serial and parallel – Audio and video and video – USB – FireWire – Connectivity • Ethernet • Modem 36 Inside Inside the System Unit • Essential electronic components used to process data • Types of Types of components: components: – – – – – Power supply Hard disk drive Motherboard CPU Expansion cards 37 The Motherboard • CPU • RAM • Expansion cards and car slots slots • Built-in Builtcomponents 38 Central Processing Unit (CPU) • • • • Referred to as the “brains” of the computer Controls all functions of the computer Processes all commands and instructions Can perform billions of tasks per second 39 Memory Memory Module • • • • Random access memory (RAM) Stores instructions and data Temporary (volatile) storage Operates in nanoseconds 40 Expansion Cards • Add functions • Provide new connections for peripheral devices • Common types: – Sound – Modem – Video (VGA) – Network (NIC) 41 Setting It All Up: Ergonomics • Ergonomics: minimizing injury or discomfort while using the computer • Steps to follow: – Position monitor correctl tly – Use adjustable chair – Assume proper position while typing – Take breaks – Ensure adequate lighting 42 Chapter Chapter 2 Summary Questions • What exactly is a computer, and what are its four main functions? 43 Chapter 2 Summary Questions • What is the difference between data and information? 44 Chapter 2 Summary Questions • What are bits and bytes, and how are they measured? 45 Chapter Chapter 2 Summary Questions • What devices do you use to get data into the computer? 46 Chapter 2 Summary Questions • What devices do you use to get information out of the computer? 47 Chapter 2 Summary Questions • What’s on the front of your system unit? 48 Chapter Chapter 2 Summary Questions • What’s on the back of your system unit? 49 Chapter 2 Summary Questions • What’s inside your system unit? 50 Chapter 2 Summary Questions • How do you set up your computer to avoid strain and injury? 51 ...
View Full Document

This note was uploaded on 01/11/2012 for the course BIOL 2021 BIOL 2021 taught by Professor Pat during the Fall '10 term at York University.

Ask a homework question - tutors are online