COMPUTER APPLICATIONS Waxahachie High School

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COMPUTER APPLICATIONSWaxahachie High School

• Introduction to Computers
• TA TEKS (1)(A), (1)(B), (1)(C), (1)(D), (1)(F),
  (1)(G), (1)(I), (2)(A), (2)(B), (2)(C)

Source Computers Tools for an Information Age
(Capron and Johnson)
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INTRODUCTION TO COMPUTERS

• LESSON OBJECTIVE
• Describe the three fundamental characteristics of
  computers.
• Describe at least four areas of society in which
  computers are used.
• Identify the basic components of a computer
  system.
• Distinguish data from information.
• Explain the various classifications of computers.

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INTRODUCTION TO COMPUTERS

• Computers have three fundamental characteristics
• Speed - Computers provide the processing speed
  essential to our fast paced environment
• Reliability - Computers are extremely reliable.
• Storage Capability - Computer systems can store
  tremendous amounts of data.

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INTRODUCTION TO COMPUTERS

• The equipment associated with a computer system
  is called hardware.
• The programs, or step-by-step instructions that
  run the machines, are called software.
• Computer programmers write programs for users, or
  end-users, people who purchase and use computer
  software.

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INTRODUCTION TO COMPUTERS

• A computer is a machine that can be programmed to
  process data (input) into useful information
  (output).
• A computer system comprises four main aspects of
  data handling input, processing, output, and
  storage.

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INTRODUCTION TO COMPUTERS
The four primary components of a computer system.
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INTRODUCTION TO COMPUTERS
Personal Computer System
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INTRODUCTION TO COMPUTERS
Input is data to be accepted in the computer.
Common input devices are the keyboard a mouse,
which translates the movements of a ball on a
flat surface to actions on the screen a wand
reader or bar code reader, which uses laser beams
to read special letters, numbers, or symbols,
such as the zebra-striped codes (UPC) on
products and a flatbed or sheet-fed scanner,
used to scan photos or documents into the
computer.
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INTRODUCTION TO COMPUTERS
A terminal includes an input device, such as a
keyboard an output device a screen and a
connection to the main computer.
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INTRODUCTION TO COMPUTERS
The processor, or central processing unit (CPU),
processes raw data into meaningful, useful
information. The CPU interprets and executes
program instructions and communicates with the
input, output, and storage devices. Memory, or
primary storage, is related to the CPU but is
separate and distinct form it. Memory holds the
input data before processing and also holds the
processed data after processing until the data is
released to the output device.
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INTRODUCTION TO COMPUTERS
Output, which is raw data processed in usable
information, is usually in the form of words,
numbers, and graphics. Users can see output
displayed on a screen, or monitor, and use
printers to display output on paper.
Monitor
Inkjet Printer
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INTRODUCTION TO COMPUTERS
Secondary storage provides additional storage
space separate from memory. The most common
secondary storage devices are magnetic disks.
Magnetic disks are floppy disks (diskettes) or
hard disks. Hard disks hold more data and offer
faster access than floppy disks. Disk data is
read and written on disk drives.
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INTRODUCTION TO COMPUTERS
3.5 Diskette
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INTRODUCTION TO COMPUTERS
Optical disk drives, such as CD-ROMs and
DVD-ROMs, use a laser beam to read large volumes
of data. Magnetic tape comes on reels or in
cartridges and is primarily used for back-up
purposes. Magnetic tape is mounted on a tape
drive.
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INTRODUCTION TO COMPUTERS
Optical Disk
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INTRODUCTION TO COMPUTERS
Peripheral equipment includes all the input,
output, and secondary storage devices that are
attached to a personal computer
(PC). Organizations use a network of personal
computers, which enables users to operate
independently or in cooperation with other
computers, exchanging data and sharing resources.
This setup is called a local area network (LAN).
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INTRODUCTION TO COMPUTERS
Users who connect their computers via the phone
lines must use a hardware device called a modem
to reconcile the inherent differences between
computers and the phone system. Individuals use
networking for a variety of purposes, especially
electronic mail, or e-mail.
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INTRODUCTION TO COMPUTERS
The Internet, sometimes called the Net, connects
users worldwide. To access the Internet, a users
computer must connect to a type of computer
called a server, which has special software
called TCP/IP (Transmission Control
Protocol/Internet Protocol) that enables
different types of computers to communicate with
one another. The supplier of the server computer,
often called an Internet service provider (ISP),
charges a fee for the access.
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INTRODUCTION TO COMPUTERS
(1) A user accesses the ISPs server computer (2)
over the phone line. (3) The server computer
communicates with the internet. (4) Requested
Internet information is returned to the user.
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INTRODUCTION TO COMPUTERS
With software called a browser, a user can
manipulate a mouse to point and click on screen
text or pictures to explore the Internet,
particularly the World Wide Web (WWW or the Web).
Each different location on the Web is called a
Web site or a site. A home page is the main page
of a Web site.
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INTRODUCTION TO COMPUTERS
Desktop computers are called personal computers
(PCs), or microcomputers. Workstations combine
the compactness of a desktop computer with power
approaching that of a mainframe. A network
computer is a limited machine that is often
referred to as a thin client.
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INTRODUCTION TO COMPUTERS
Notebook computers are small portable computers
heavier versions of the notebook are called
laptop computers. Personal digital assistants
(PDAs), are hand-held computers that enable users
to keep track of appointments and other
information. Pocket PCs have the capability of
running modified versions of some desktop
software.
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INTRODUCTION TO COMPUTERS
PDA
Notebook
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INTRODUCTION TO COMPUTERS
Midrange computers, formerly referred to as
minicomputers, are multi-user computers designed
to serve the needs of medium-sized
organizations. Large computers called mainframes
are used by businesses such as banks, airlines,
and manufacturers to process large amounts of
data quickly. The most powerful and expensive
computers are called supercomputers.
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INTRODUCTION TO COMPUTERS
Supercomputer