Getting Started, Part 1

Objectives

When we complete this section, you should be able to:

Describe the components of a computer system.
Define the terms used to measure the capacity and speed of a microprocessor, memory and storage
Describe the contributions of IBM, Microsoft, and Intel in the evolution of the PC
Discuss consideration in the purchase of a computer system.
Distinguish between system software and application software

Computer Literacy

What is computer literacy?
What is literacy?
Look up literate at www.webster.com.
Look up literacy too.
To me, this includes:
- A knowledge of from where the dicipline came.
- A basic understanding of the terminology of the dicipline. (terms and definitions)
- An understanding of the phusical hardware. (the physical stuff, what it is and what it does)
- An understanding of how to use some of the applications.

Some History

Look up the definition for computer.
Analog vs Digital
- What is an analog clock?
- What is a digital cloc?
- What is the difference?
- Which is more accurate? Trick question.
- Which can be read more accurately.
- analog representing data by a physical quantity
- digital representing data as a number.
- Think of a flood gauge, or rain gauge.
- Think of a ruler, 14 and 3/16 + a little bit.
the first computers were analog.
- Fingers, stones, bones, ...
- Abacus
- These probably don't fit into the book's definition of a computer.
- computer an electronic device that accepts data, processes that data to produce information. It operates under the control of a program that is stored internally within the computer's memory.
- Why do the above devices fail to meet this definition?
In your book is a picture of Charles Babbage's Analytical Engine
- An analog computer
- Almost built in the late 1800's
- Could store both data and program
- Failed because technology was not equal to theory.
Mondern electronic computers
- Were first built in the lat 1940's
- Have been through a number of "generations"
  - 0th generation - electro-mechanical
  - 1st generation - vacuume tubes
  - 2st generation - transistors
  - 3rd generation - microchip
Computers once were classified by size
- Mainframes: $500,000 and up. Used for Corporate Data Processing
- Minicomputers: $100,000 - $500,000. Division Data Processing
- Workstations: $5,000 - $100,000. Scientific Calculations
- Microcomputers: Up to $5,000. Personal use.
- These are really no longer valid.

Most Computers

Can be broken into a number of parts
- CPU - Central Processing Unit
- Memory - RAM (Random Access Memory)
- Secondary Storage (The hard drive)
- Input Devices (keyboard, mouse ...)
- Output Devices (Monitor, printer)
Run a program called the Operating System
- This program manages the computer
- Provides a way for the user to interact with the computer
- Examples
  - Windows (95, 98, NT, 2000, ME, XT)
  - Unix (LINUX, Solaris, HPUX, AIX )
  - VM, VMS
  - A few others.
Run application programs
- Netscape/IE
- The program that sends web pages (A web server)
- Word
- Many many others.

Representing Data Digitaly

We use a base 10 number system, digits 0 -9
Computers use base 2, digits 0 and 1.
Why?
A single Binary Digit is called a bit
8 bits form a byte
About 1000 bytes for a kilobyte or 1K
About 1 million bytes form a megabyte or 1M (meg)
Characters are encoded using ASCII Americal Standard Code for Information Interchange.
Letter ASCII Code

A 0100 0001

B 0100 0010

C 0100 0011

Letter	ASCII Code
A	0100 0001
B	0100 0010
C	0100 0011

Example
      Dan is
      0100 0100 0110 0001 0110 1110 
          D         a         n

Parts of a PC

Some History First
- 1975 ALTAIR computer kit, build it your self.
- 1976 First APPLE I introduced.
- 1977 Tandy and Commodore begin selling pcs.
- 1977 Microsoft founded.
- 1978 Intel introduces the 8086
- 1981 IBM begins selling IBM PCA
- 1982 IBM Clones begin arriving, Compaq is an early player
- 1985 Intel introduces the 80386
The Parts
- Motherboard - this is the frame on which everything is put.
  - Directly attached is the processor, chip or CPU Central Processing Unit.
    - Measured in Gigahertz
    - 1 to 2 GHz
  - Main Memory is also directly attached.
    - Measured in Megabytes
    - 128 is a minimum
  - It has a number of expansion slots where other devices (modems, sound and graphics cards, ...) can be attached.
- A hard drive (or several) are plugged into the motherboard
  - Measured in gigabytes
  - 10 - 80 is standard
  - 10 is probably low today
- There are a number of drives that support removable media
  - Floppy Drive
  - zip drive
  - CD player
  - DVD player
  - Tape Drive for backup
- The motherboard is mounted in a case, which contains a
  - Power supply
  - Fans
  - Space to mount all of this stuff.
- A number of cards can be plugged into the expansion slots or their functionality can be built into the motherboard.
  - A video card or graphics card goes into the AGP slot
  - sound card
  - modem
  - LAN card or network card
  - Many specialized cards
- There are a number of I/O devices that attach externaly to the machine.
  - Monitor
  - Keyboard
  - Mouse
  - Printer
  - Joystick
A word about the CPU
- CPUs are manufactured by different companies
  - INTEL
  - AMD
  - HP
  - And Others
- CPUs are in different families
  - Pentium
  - Celeron
  - Xeon
  - PA-Risc
  - and others
- You can't compare CPUs from different families directly
- CPUs have a speed that they operate
  - This is in megahertz
  - This is millions of cycles per second
  - Currently up to 2 Gigahertz are supported
  - This is equivelent to 2 billion instructions per second
  - Add, get from memory, write to memory ...
- Moore's Law Perfomance will double every 18 months.
  - Stated in 1965
  - Has held true since then.
  - Means that things become obsolete very quickly.
  - Programs expect to have more processing power available to them
  - If you build it, they will come (or use it as the case may be)

Purchasing a PC

You have a large number of choices
- Purchase from someone like Dell or Gateway .
- Purchase from a local company.
- Radio Shack, Sears ...
- Buy the pieces and build it yourself.
You should consider support options as well.
- Warranty
- User support
Take a look at
- dell.com
- wvccsi.com