Intro to Computers

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Intro to Computers

• Technology Applications
• North Ridge Middle School
• Use the information in this presentation to fill
  out the worksheet you are given.

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What is a Computer?

• A computer is a machine that
• receives input (data)
• performs processing
• produces output (information)
• Without any one of these the computer would be
  worthless

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Examples of Input, Processing Output
Input
Processing
Output
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Disks, Disk Drives and Permanent Storage

• No work on the computer is stored permanently
  unless it is saved from the computers memory to
  a diskette, hard drive or some other storage
  device.
• Disk drives are identified by letter
• The diskette drive is letter A
• The hard drive is usually letter C

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Personal Computer Hardware

• Hardware refers to the pieces of equipment that
  make up the computer system.
• Examples of computer hardware components
  Drives, Monitor, Keyboard, Mouse, Printer, Bus
  expansion slots cards, CPU and Memory Chips,
  Speakers

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Personal Computer Hardware
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Hardware

• The motherboard is the largest circuit board in
  the PC. It contains millions of electronic
  circuits on a chip of silicon.
• The CPU (Central Processing Unit) is a chip on
  the Motherboard that performs mathematical
  calculations and logic functions. The CPU is
  often called the brain of the computer

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Hardware (continued)

• RAM (Random Access Memory) is temporary memory
  where programs and data are while they are being
  used.
• When a document is opened it is loaded into RAM.
• When you save a document the CPU copies the
  document that is in RAM to permanent storage.
• When the power is turned off the information in
  RAM is lost.
• The storage capacity of RAM is measured in
  megabytes.

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Hardware (continued)

• Some hardware components are primarily input
  devices and some are primarily output devices.
• The following is a list of 10 common hardware
  components and whether they are input devices,
  output devices or both.

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Input and Output Devices

• Monitor an output device that displays input and
  the results of processing.
• Mouse an input device that controls a pointer on
  the monitor. You can click the mouse to give the
  computer input.
• Keyboard an input device with letters, numbers,
  symbols and special keys used to input data and
  type text.

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Input and Output Devices (contd)

• Hard disk (Hard drive) permanent storage device
  usually installed in the system unit. It can be
  used to receive input and produce output.
• Diskette Drive a drive that can read a removable
  disk. It can be used to receive input and
  produce output.
• CD-ROM (Compact Disk Read Only Memory) a disk
  that can be used to input data into the computer

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Input and Output Devices (contd)

• CD-RW (Compact Disk Read/Write) a disk that
  can be used to input data (read) or output or
  store data (write).
• Modem (Modulate/Demodulate) a piece of hardware
  that converts an incoming signal so the computer
  can read it (input) and converts an outgoing
  signal so it can be sent over phone lines
  (output).

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Input and Output Devices (contd)

• Printers one of most common output devices.
  Produces paper copy (hard copy) of output.
• Scanners input device which lets you create
  digital files from pictures, drawings or text.

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Types of Printers

• Laser printers which use copier-like technology
  to spread patterns of toner and make it stick to
  the paper with heat.
• Inkjet printers that spray ink onto paper to
  produce the output.
• Plotters printers that use needles to draw on
  paper. They are frequently used by engineers to
  produce schematic drawings.

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Controlling Windows

• Via the Keyboard used to enter data and to
  issue commands to the computer.
• Keys on the Keyboard
• Function Keys the twelve keys located across the
  top of the keyboard that are labeled F1-F12. They
  perform specific tasks depending on the software
  you are using.
• Escape Key used to back out or interrupt a task.

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Controlling Windows

• Via the Mouse a small, hand-held device that is
  used to control the pointer on the screen.
• There are Seven Main Mouse Actions
• Point
• Click
• Right-click
• Double-click
• Drag
• Right-drag
• Scroll

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Bits and Bytes

• Personal computers operate through a number of
  on/of switches called binary digits or bits.
• Everything that a computer does is accomplished
  by switches that are either turned on or off.
• A string of 8 bits is equal to one byte. Each
  byte is translated by the computer into a letter
  or action.
• A 0 represents a switch that is turned off and a
  1 represents a switch that is turned on.

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File Size and Storage Capacity

• Computers work with digital information
  everything is converted to 0s and 1s
• Each 0 or 1 is a bit
• A byte is the most common measurement of storage.
• 1 byte 8 bits
• 1 kilobyte 1 thousand bytes
• 1 megabyte 1 million bytes
• 1 gigabyte 1 billion bytes
• 1 terabyte 1 trillion bytes

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Processor Speed

• The speed of a computer is measured in gigahertz
  or megahertz.
• Megahertz millions of cycles per second
• Gigahertz billions of cycles per second

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Software

• Software refers to the instructions that allow a
  computer to run. There are two categories of
  software
• Operating System allows the computer to boot
  controls and manages the computer by translating
  instructions into a language the computer can
  understand. In our lab we have Windows XP
• Application Software software that allows you
  to perform specific tasks such as write a letter,
  play a game or create a spreadsheet.

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Types of Computer

• Supercomputer (largest in size)
• Mainframe
• Minicomputer
• Microcomputer (Personal Computer)
• PC
• Laptop
• Handheld

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Supercomputer

• Used primarily by military and scientific
  agencies weather forecasting, simulations (wind
  tunnel, nuclear detonation)
• Used when there is a need for high speed and
  intensive calculation

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Supercomputer
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Supercomputer
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Mainframe

• Used primarily by businesses credit card
  companies, bank accounts, insurance, airline
  reservations)
• Used when the computations are simpler but there
  are huge amounts of data. (simpler calculations
  but more of them)

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Mainframe
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Minicomputer

• Used by more than one person at a time
• Now called midrange systems, workstations and
  servers
• Being replaced by microcomputers and LANs (Local
  Area Networks)

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Minicomputer
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Microcomputer

• Most commonly used Microcomputer is a Personal
  Computer or Desktop Computer.
• Usually single user machines
• Other Microcomputers include video game
  consoles, laptop computers, and many types of
  handheld devices may all be considered examples
  of microcomputers

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Microcomputers Handheld Devices

• Handheld devices are pocket-sized computing
  devices that are rapidly gaining popularity as
  the access to information in every walk of life
  becomes more and more mission critical. Along
  with mobile computing devices such as laptops and
  smartphones, PDAs represent the new frontier of
  computing as desktop computers find less and less
  favour among every day users.The following are
  typical handhelds
• Smartphone
• Personal digital assistant
• Mobile phone
• Handheld game console

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Handheld Devices
Nokia Smartphone
Mobile or Cell Phones
Tungsten PDA
Handheld Game Console
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Computer Careers

• Computers require specially trained personnel to
  keep them running efficiently. The following are
  some computer related careers
• Application Programmers people who ensure that
  the programs an organization needs are created,
  maintained and improved.

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Computer Careers (contd)

• Network Administrator people who specialize in
  making sure that a companys network operates
  efficiently.
• Help Desk Professionals people who are trained
  to provide help to users of applications.
• Web site designers and programmers people who
  decide what Web pages should look like and write
  the code to create them.