ITEC Orientation

1
How does a computer work?

• ITEC Orientation
• Introduction to Computers
• Ms. Denise
• Sept. 2004

2
What is a Computer?

• A computer is a electronic tool.
• Without electricity your computer would just be
  a collection of plastic, silicon and metal.
• When you turn on the computer electricity flows
  through the circuit boards and microprocessors.
• Because a computer is dependent on electricity
  to operate a computer can only perform tasks
  based on the presence or absence of electricity
  in a circuit. The computer sees an on state as
  1 and off as 0.

3

• Computer memory and storage is always digital,
  which means all data and numbers are stored as
  strings of binary digits (0s and 1s).
• The following terms refer to the different
  amounts of digital storage.

4
How much data do these storage units hold?
5
Computers perform five basic operations

• Information is

• Communicated

• Stored

• Input

Output
Processed
6
Input devices are used to enter data into a
computer. They allow you to give commands to the
computer, and allow the computer to access
information from external (outside) sources.
Input
7
The Central Processing Unit (CPU) is the
main chip in a computer. The CPU processes
instructions, performs calculations and manages
the flow of information through a computer
system. The CPU communicates with input,
output and storage devices to perform tasks.
Process
8
    Processing devices perform most of the work
inside of the computer, from simple arithmetic to
complex calculations needed for graphics and
animation. Processing devices also control and
coordinate all of the activity between the rest
of the computers components.  
9
Storage devices allow the computer to hold
information permanently. (Also while the computer
is turned off).
Storage
10
Communication devices enable a computer to
connect to other computers. 
Communication
11
Output devices convert the results of processing
into a form that is understandable to humans.
Output
12
The computer is composed of hardware, software
and an operating system.
The operating system is a special type of
software that allows the hardware and software to
work together.
Operating System
Software Application/Program
Hardware Computer
13

• Hardware is any part of a computer system that
  you can see or touch (or break!)

Hardware
The basic components of a computer are
Inside the computer box

• Motherboard
• Hard Drive
• Floppy Drive
• CD Drive
• Mouse
• Keyboard
• Monitor

14
Computer hardware generally cannot do anything
unless it is running a special type of software
called an operating system.
Operating System

• The operating system is a basic type of
  software that co-ordinates how applications and
  the hardware interact.
• An application is a piece of software designed
  to carry out a specific task (word-processing,
  spreadsheet, database, or game for example).

15
A computer is not intelligent. It must be given
specific, detailed instructions about how to
perform any task. This group of instructions is
called a computer program, or software.
Computer software is the key to the productive
use of computers. With the correct software, a
computer can become a valuable tool. There are
three basic categories of computer software -
system software, application software and
development software.
Software
16
System software allows the computer to perform
the most basic operations (controlling the input,
output and storage devices). For this reason,
these programs are collectively known as
Operating Systems.
System software

• To make the computer easier to use, many
  operating systems provide small pictures, or
  icons that represent programs, documents, and
  other objects. The icons are selected by using a
  mouse, or other pointing device.
• This is called a Graphical User Interface, or GUI
  (pronounced "gooey").

17
Development software is used to "create" the
other two types of software (system and
application).
Development software
18
Application software is used to produce
information for a specific purpose, such as in a
business or educational environment. Some
businesses require application software that must
be specially designed. Other application
software "packages" are general in nature, and
can be bought from computer stores.
Application software
19
A user has complete control over the
computers operation 

• You can
•  Add, remove and upgrade hardware and software
  components.
•  
•   Create new applications, and change existing
  ones.
•    Connect to other computers, via a network,
  or the Internet.