1. Computer Hardware & Processing Outside the Box CSC 101 1.0 September 9, 2010

2. Computers Are Data-Processing Devices A computer’s four major functions: – Gathers data (users input data) – Processes data into information – Outputs data or information – Stores data and information Plus – Computers can communicate with other computers

3. Data vs. Information Data: Representation of a fact, figure, or idea Information: Organized, meaningful data

4. Bits and Bytes: The Language of Computers Bit Binary digit 0 or 1 Abbreviation “b” Byte 8 bits Abbreviation “B” Each letter, number, and character is a string of eight 0s and 1s

5. Counting Bytes NameAbbreviationNumber of BytesRelative Size ByteB1 byteCan hold one character of data. KilobyteKB1,024 bytes (2 10 bytes)Can hold 1,024 characters or about half of a double-spaced typewritten page. MegabyteMB1,048,576 bytes (2 20 bytes)Can hold approximately 768 pages of typed text. GigabyteGB1,073,741,824 bytes (2 30 bytes)Approximately 786,432 pages of text; 500 sheets of paper is approximately 2 inches, so this represents a stack of paper 262 feet high. TerabyteTB1,099,511,627,776 bytes (2 40 bytes)This represents a stack of typewritten pages almost 51 miles high. PetabytePB1,125,899,906,842,62 bytes (2 50 bytes)The stack of pages is now 52,000 miles high, or approximately one-fourth the distance from the Earth to the moon. ExabyteEB1,152,921,504,606,846,976 bytes (2 60 bytes) The stack of pages is now 52 million miles high, or just about twice the distance between the Earth and Venus. ZettabyteZB1,180,591,620,717,411,303,424 bytes (2 70 bytes) The stack of pages is now 52 billion miles high, some 20 times the distance between the Earth and Pluto.

6. Computer Hardware & Computer Software Computer Hardware Anything you can kick Computer Software Intangible instructions that tell the hardware what to do. – Systems Software – Applications Software

7. Basic Computer Hardware Components System Unit – everything in the box – Motherboard, CPU, memory Peripheral Devices – everything outside of the box – Keyboard, mouse, monitor, printer Storage Devices – where data/information gets stored – Hard drive, CD/DVD, flash drive, memory cards

8. Input Devices Translates what humans understand into a format the computer understands Different types of devices for different types of data – Keyboard – Mouse/pointing device – Microphone – Scanner – Digital camera – Stylus

9. Keyboards Used for entering text and commands. The QWERTY layout is standard on most PCs. Enhanced keyboard features include number, function, and navigation keys. Notebook keys are smaller and use a function key to expand functionality.

10. So what is this??

11. More Specialty Keyboards Virtual laser keyboard Configurable keyboard

12. Point and Draw Devices Optical mouse – Needs no mouse pad – Doesn’t need cleaning Trackball – Easier on wrists – Stays stationary on desk

13. More Point and Draw Devices Wireless mouse – Uses radio or light waves Touchpad – When a mouse just won’t do

14. Other Text and Command Input Devices Game controllers Touchscreens Digital pens

15. Image Input Devices Digital cameras, camcorders, and cell phones Still images Video Webcams Live video

16. Sound Input Device Microphones are used for: – Podcasts – Video-conferencing – Internet phone calls – Speech recognition

17. Output Devices Convert what the computer understands into a format that humans understand Output can be in two formats Hardcopy – tangible Printouts Softcopy – in tangible Video, sound, images on monitors

18. LCD Monitors LCD – Liquid Crystal Display Screens are grids made up of millions of pixels Each pixel is represented by a bit pattern comprised of a combination of red, green, and blue Liquid crystal is sandwiched between two transparent layers to form images

19. LCD Monitor Characteristics Resolution – total number of pixels, can be changed Screen size – 21” monitor - 1680x1050 pixels – 19” monitor - 1440x900 pixels or 1280x1024 pixels – Wide screen vs. standard 4:3 ratio Viewing angle – visibility from the side Contrast ratio – brightest white to darkest black Brightness – greatest amount of light when displaying pure white Response time – time it takes for a pixel to change color

20. Printer Categories Impact printers – Dot-matrix Nonimpact printers – Inkjet – Laser Specialty printers – All-in-one – Plotters – Thermal

21. Nonimpact Printers Inkjet Less expensive device Print high-quality color images cost effectively Laser More expensive device Faster printing speed Color lasers are becoming less expensive

22. Printer Characteristics Speed (ppm) Resolution (dpi) Color output Memory Use and cost Cost of consumables

23. Storage Devices Non-volatile – Almost permanent Types of computer storage devices – Internal hard drive – USB flash drive – Memory cards – Optical drive – External hard drive – Online storage Secondary storage

24. Hard Drive May be internal or external – Internal is faster Storage capacity is up to 2 terabytes (TB) Access time is measured in milliseconds Data transfer rate is measured in megabits or megabytes per second

25. How a Hard Drive Works Composed of coated platters stacked on a spindle Data saved to the disk: Pattern of magnetized spots – Spots = 1 – Spaces = 0 Spots are translated into data

26. Optical Storage Optical media: Store data as tiny pits burned into a disc by a laser – Pre-recorded CD-ROM, DVD-ROM, BD-ROM – Recordable CD-R, DVD-R, BD-R – Rewritable CD-RW, DVD-RW, BD-RE Uses a burner to write to optical media Uses two lasers to read optical media

27. Flash Memory Flash / thumb drive Memory cards Electron grid / gates High storage capacity Use very little power Must unmount before removing from computer Can cause security concerns

28. Online Storage Data stored on the Internet Inexpensive Data backup Can access data anywhere Can be password protected

29. All Storage Media Will Fail Back up your data!