1. Introduction To Computers: Hardware and Software
In this section of notes you will learn how the basic parts of a computer work as well what are the fundamental categories of computer programs

2. What Is Hardware?
The physical components of a computer system e.g., a monitor, keyboard, mouse and the computer itself.

3. Basic Units Of Measurement
Bit
binary digit
smallest unit of measurement
two possible values
Byte
8 bits
Show on the board how the number of bits translates to the amount of information that can be represented (number of possible combinations)
Word
The number of adjacent bits that can be stored and manipulated as a unit
32, 64 for home computers, 128 for the most powerful

4. Large Units Of Measurement (Memory, Storage)
Note: use powers of two because computer memory and storage are based on the basic unit (bit).
Kilobyte (kB) – a thousand bytes (1,024 = 210)
Megabyte (MB) - a million (1,048,576 = 220)
Gigabyte (GB) – a billion (1,073,741,824 = 230)
~ A complete set of encyclopedias requires about 600 MB of storage
Terabyte (TB) – a trillion (1,099,511,627,776 = 240)
~ 20 million four-drawer filing cabinets full of text

5. Small Units Of Measurement (Speed)
millisecond (ms) – a thousandth of a second (1/1,000 = 10-3)
microsecond (μs) - a millionth of a second (1/1,000,000 = 10-6)
nanosecond (ns) – a billionth of a second (1/1,000,000,000 = 10-9)
Millisecond – hard drive seek time speeds (track-track)
Nanosecond – speed of RAM

6. High Level View Of A Computer

7. Input

8. Input Devices Used by a person to communicate to a computer.
Person to computer

9. Example Input Devices Keyboard Mouse Need not be mundane! (A Jouse)
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10. Processor

11. Processor
The brains of a computer
(maybe not…)
A real processor

12. Processor Speed Determined by:
Type of processor e.g., Pentium III, IV, AMD Duron, Athalon
Clock speed
1 Hz = 1 pulse is sent out each second (1 second passes between each pulse)
10 Hz = 10 pulses are sent out each second (0.1 seconds passes between each pulse) :
25 MHz machine = 25 million pulses sent out each second ( seconds between each pulse or 40 ns between pulses)

13. The Processor And The Computer
Control Unit
Directs the flow of data traveling between the different parts of the computer
ALU
- If the control unit encounters information that requires mathematical calculations or a logical operation to be performed then it is sent to the ALU.
Image from Peter Norton's Computing Fundamentals (3rd Edition) by Norton P.

14. Memory

15. RAM
Volatile
Used for temporary storage
Typical ranges 256 MB ~1 GB

16. RAM (2) Means direct access to any part of memory
Picture from Computers in your future by Pfaffenberger B

17. How Does RAM Work?
Like a leaky bucket
From

18. How Does RAM Work? Like a leaky bucket Transistor Capacitor
From

19. RAM: A Collection Of Capacitors
A capacitor

20. Types Of RAM Old versions of RAM EDO RAM SD-RAM Slowest
For older computers
SD-RAM
Faster
Was the former standard
EDO RAM
Name means it allows another access to memory to start while the previous access is still being completed
60 ns
Pentium I
4MB – 64 MB chips
SD-RAM
Synchronous RAM (runs at processor speed)
7 – 8 ns
Pentium I onwards
32 – 512 MB chips
P100 & P133 MHz – speed information is sent
Pictures from

21. Types Of RAM (2) Newer version of RAM DDR-RAM (Double Data Rate RAM)
Double the speed of SD-RAM
Originally exclusively used with
AMD processors
RD-RAM (Rambus Dynamic RAM)
Produced by Rambus
Fast!
Used with Pentium 4 powered
computers
DDR-RAM
Like SD-RAM but able to send data twice as fast
PC-200MHZ (The PC-1600) and PC-266MHZ (The PC-2100). Now up to 333 MHz.
Originally used only with AMD Athalon and Thunderbird (but no longer)
128 MB – 1 GB chips
Less than 1 ns
RD-RAM
128 MB – 1 GB
400 or 800 MHz
Pictures from

22. Storage

23. Storage Vs. Memory? Memory (e.g., RAM)
keep the information for a shorter period of time (usually volatile)
faster
more expensive
Storage (e.g., Hard disk)
the information is retained longer (non-volatile)
slower
cheaper

24. Categories Of Storage 1) Magnetic 2) Optical Floppy disks Zip disks
Jazz drives
Hard drives
2) Optical
CD-ROM
DVD

25. Magnetic Drives: A Hard Drive In Action

26. Magnetic Drives: Storage Capacities
Floppy disks
~ 1 MB
Zip disks
100 or 250 MB
Jazz drives
1 – 2 GB
Hard drives
~20 – 120+ GB

27. Optical Drives: Reading Information
Pits and land don't represent info.
Land represents 0's
Transition (pits-land, land-pits) represents a 1.

28. Optical Drives: Recording and Reading Information

29. Optical Drives: Re-writing

30. Optical Drives: Re-writing

31. Optical Drives CD's DVD-ROM ~ 700 MB storage CD-ROM (read only)
CD-R: needs a CD-burner to create (record) to a CD
CD-RW: can write and erase CD to reuse it (re-writable)
DVD-ROM
~ 3.8 – 17 GB storage
DVD- ROM (read only)
Many recordable formats (e.g., DVD/CD-RW, DVD-RAM, DVD-R, CD-RW etc)

32. Output

33. Output Devices
Displays information from the computer to the a person.

34. The Most Common Output Device: The Monitor
Types of computer monitors
CRT's (Cathode Ray Tube)
LCD's (Liquid Crystal Display)

35. CRT's Monitors
Images are displayed with dots (pixels) drawn with light "guns"
Picture from Computer Confluence by Beekman G.

36. LCD Monitors Employ a conductive grid for each row and column
The meeting of a row and column allows light to be emitted (a pixel can be seen)

37. Colour LCD Monitors Use three subpixels: One wire for each row
One wire for each subpixel
One colour filter for each colour (red, blue, green)

38. Some Determinants Of The Quality Of Monitors
Size
Resolution
Color depth
Dot pitch

39. 1) Monitor Quality (size)
Measured diagonally

40. 2) Monitor quality (resolution)
Columns of pixels x Rows of pixels
For a given monitor size, the higher the resolution the sharper the image
Col 1, Row 1
Col 2, Row 1
Col 3, Row 1 …
Col [c], Row 1
Col 1, Row 2
Col [c], Row 2
Col 1, Row 3
Col [c], Row 3 :
Col 1, Row [r]
Col 2, Row [r]
Col 3, Row [r]
Col[c], Row[r]

41. 3) Monitor Quality (Color Depth)
The number of possible colors that can be displayed for each pixel.
e.g. monochrome (single color) 1
2 possible values
Uses up 1 bit of space

42. 3) Monitor Quality (Effects Of Color Depth)
2 colours
16 colours
256 colours
16 million colours

43. 4) Monitor Quality (Dot Pitch)
Dot pitch is the distance between the center of each color dot (mm)
dot pitch

44. Refresh rate of monitors
How fast the screen is redrawn
(70 Hz / 70 times per second is usually a good minimum)

45. All The Basic Parts Together
Diagram from

46. The Motherboard
ISA/PCI – for older/newer way of hooking up things like sound cards, internal modems etc
Connectors – hard and floppy drives, CD-ROM
Memory – SIMM (old - smaller) and DIMM (newer – larger)
Diagram from

47. Printers Common types Inkjet Laser
Note: By default on the CPSC network you only have access to text-only printers (do not print formatted text or graphics on them!) You can pay a minimal fee to access the laser printers.

48. How Inkjet Printers Work.
Use a series of nozzles to spray drops of ink directly on the paper
Print heads
Slots for print cartridges
Ink nozzles
Picture from

49. How Laser Printers Work
Use a laser to produce patterns on an ink drum using static electricity
The drum is made out of photoreceptive material (ability to conduct electricity affected by the exposure to light – photocopiers work this way)
The drum is give a positive electrical charge by the Corona wire
Then as the drum rotates a laser is shined across different parts of the surface of the drum
This discharges the electrical charge and ‘draws’ characters and images onto the drum (the discharged areas)
The drum is then covered with toner (fine black ink) which sticks only to the discharged areas
(Kind of like putting ink on parts of pop can and rolling it in flour)
The drum is then rolled over a piece of paper and corona wires under the paper employ another electrical charge to pull the toner off of the drum onto the paper.
The fuser heats the paper to melt the toner powder and fuse the toner to the paper (that’s why the paper comes out warm)
The discharge lamp removes the electrical charge from the printer drum
Diagram from

50. Software The instructions that tell the hardware what to do.
Balance my check book.
Do taxes
Print out my resume
: :

51. Categories Of Software
Application programs (applications)
Operating systems
Compilers

52. 1) Common Types Of Application Programs
Word processors
Spreadsheets
Databases
Presentation software
Web browsers
: :

53. 2) Operating Systems: What Do They Do?
Act an an intermediary between the user and the hardware
Manage the resources of the computer
Some may act to secure some parts of the computer

54. Operating Systems: The Intermediary Between The User And The Hardware

55. Operating Systems: Manage System Resources (1)
e.g., Processor time
A = B + C

56. Operating Systems: Manage System Resources (2)
e.g., Memory management
RAM
A = B + C

57. Operating Systems: Securing The Computer (not done)
Single (faceless) user – security less of an issue
Claude Rains from Phantom of the Opera
My resume

58. Operating Systems: Securing The Computer (done)
Multiple users – security is more important
Bill
Mary
George
Mary's assignment
Bill's assignment
George's assignment

59. 3) Compilers (Real-World)
Real life translation
Same to you buddy!
Merry Christmas and Happy New Year!
Huh?

60. 3) Compilers (Computers)
Anybody who has this executable on their computer can then run (use) it.
1) A programmer writes a computer program
3) An executable program is created
2) The compiler translates the program into a form that the computer can understand

61. Summary What is hardware? What are the basic parts of a computer?
What are some common input devices?
What is the purpose of the processor? What are some examples of modern processors and their speeds?
How does computer memory work?
What are some common types of computer storage devices?
What are the main types of computer monitors and how do they work?
What are some of the factors that determine the quality of computer monitors?
What is software?
What are the main categories of software
What are application programs?
What do operating systems do?
What is a compiler?