Transcript What are the categories of computers?

SAK1002
Information Technology
Applications
Objectives of this course:
•
Student can understand about
computer designs and its processes.
•
Student know how to use current
applications.
Chapter
1
INTRODUCTION
Objectives of this chapter:
You can…
Define the term, computer and its
advantages
Identify the components of a computer
Know its history
Identify the element of information
system
Discuss computer application in society
Overview
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This chapter covers
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Computer definition and operations.
Computer generations.
The components of a computer.
Categories of computers
Computer impact on society.
1.1 Definition and Operations
1.1 Definition and
Operations
What Is a Computer and What Does It Do?
Computer: A programmable, electronic device that accepts
data, performs operations, presents the results, and can
store the data or results
Accepts data
Raw facts, figures, and
symbols
Processes data into
information
Data that is organized,
meaningful, and useful
Produces and stores results
Computer operations
• Input—entering data into the computer
• Processing—performing operations on the data
• Output—presenting the results
• Storage—saving data, programs, or output for
future use
Computer operations
Advantages of Using
Computers
Speed
Reliability
Storage
Consistency
Communications
Disadvantages of Using
Computers
Violation of
Privacy
Impact on
Labor Force
Health Risks
Impact on
Environment
1.2 Main Components of a
Computer
Main components of a
Computer
Hardware
Software
• Hardware
– The physical parts of a computer
– Can be internal (located inside the system unit) or external (located
outside of the system unit)
• Software
– Programs or instructions used to tell the computer hardware what to do
Computer Hardware
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Input device:

Hardware used
to enter data
and instructions
Refer to your textbook for more
pictures and explanations for
better understanding.
Computer hardware (cont’d)
•
Output device:

Hardware that
conveys
information
to one or more
people
Refer to your textbook for more
pictures and explanations for
better understanding
Computer components
(hardware)
•
System unit

Case
containing
electronic
components
used to process
data
Refer to your textbook for more
pictures and explanations for
better understanding
Computer hardware (cont’d)
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Two main components on the motherboard:
Processor
Also called a Central Processing Unit (CPU)
The electronic component that interprets and carries
out the basic instructions that operate the computer
Memory
Consists of electronic components that store
instructions waiting to be executed and data needed by
those instructions
Computer hardware (cont’d)
•
What is storage?
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Holds data, instructions, and information
for future use
Storage media
Physical material on which data, instructions,
and information are stored
Storage device
Records and retrieves items to and from
storage media
Computer hardware (cont’d)
• Floppy disk and USB flash drive
Floppy Disk
Thin,
circular, flexible
disk enclosed in a squareshaped plastic shell
Stores
up to about 1.4
million characters
USB Flash Drive
Provides
much
greater storage
capacity than a
floppy disk or
Zip® disk
Small
and lightweight
enough to be transported
on a keychain or in a
pocket
Computer hardware (cont’d)
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Hard disk
– Provides greater
storage
capacity than a
floppy disk, Zip disk, or
USB flash drive
– Most are housed inside
of the system unit
Computer hardware (cont’d)
•
Compact disc
– Flat, round, portable metal disc
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p. 9 Fig. 1-5
CD-ROM
DVD-ROM
Computer hardware (cont’d)
• Communications device
Hardware component that
enables a computer to
send and receive data, instructions,
and information
Occurs over cables, telephone
lines, cellular radio networks,
satellites, and other
transmission media
Computer Software
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What is software?
Consists of a series
of instructions that
tells the computer
what to do
Also called a
program
Computer Software (cont’d)
•
What is a graphical user interface (GUI)?
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Allows you to
interact with the
software using
graphics and icons
Controls how you
enter data and how
the screen displays
information
Computer software (cont’d)
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What is system software?
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Programs that control or maintain the operations of the
computer and its devices
Operating System (OS)
is a set of programs
that coordinates all
activities among
computer hardware
devices and allows
users to run
application software
p. 15-16
Utility Programs allow the user to
perform maintenance-type tasks
usually related to managing a
computer, its devices or its programs
Computer software (cont’d)
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Application software
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Programs that perform specific tasks
for users
Word
Processing
Spreadsheet
Database
Presentation
Graphics
Computer software (cont’d)
JavaScript
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Programmer
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Someone who develops
application or system software
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Programmer writes
the instructions to
direct the computer to
process data into
information
Web application
1.3 Categories of Computers
Categories of Computers
What are the categories
of computers?
Personal Computers
(desktop)
Mobile Computers and
Mobile Devices
Game Consoles
Servers
Mainframes
Supercomputers
Embedded Computers
Categories of computers
(cont’d)
1. Personal Computers
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Designed so all of the components fit entirely on or under a
desk or table
 Apple Macintosh
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PC and compatibles
use the Windows
operating system
uses the Macintosh
operating system
(Mac OS)
Categories of computers
(cont’d)
2. Mobile Computers
Notebook computer
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Portable, small enough to fit on
your lap
Also called a laptop computer
Generally more expensive than
a desktop computer
Categories of computers
(cont’d)
Tablet PC
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Resembles a letter-sized slate
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Allows you to write on the screen
using a digital pen
useful for taking notes
Categories of computers
(cont’d)
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What are mobile devices?
Small enough to
carry in a pocket
Categories of computers
(cont’d)
• Mobile Device
Handheld computer
Small
enough to fit
in one
hand
Used
by mobile
employees such as
meter readers and
delivery people
Categories of computers
(cont’d)
• Mobile Device
Personal digital assistant (PDA)
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Provides personal organizer functions
• Calendar
• Appointment book
• Address book
• Calculator
• Notepad
Categories of computers
(cont’d)
• Mobile Device
Smart phones
A smart phone is
an Internet-enabled
telephone that usually
provides PDA capabilities
Categories of computers
(cont’d)
3. Game consoles
Mobile computing device designed for
single-player or multiplayer video games
Categories of computers
(cont’d)
4. Servers
A server controls access to network
resources and provides centralized
storage
Mainframe Very powerful,
expensive computer that supports
thousands of computers
Supercomputer The fastest, most
powerful, most expensive computer.
Used for applications requiring
complex mathematical calculations
Categories of computers
(cont’d)
5. Mainframes
– A high-performance computer used for large-scale computing purposes
that require greater availability and security than a smaller-scale
machine can offer
Categories of computers
(cont’d)
6. Supercomputers
– The fastest type of computer
– Very expensive and employed for specialized applications that require
immense amounts of mathematical calculation
Categories of computers
(cont’d)
7. Embedded computers
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A special-purpose computer that functions as a
component in a larger product
1.4 Computer History
Computer History
• The computer that we use now is a fairly recent
invention
• The history of computers is often referred to in
terms of generations, from pre-computers and
early computers (before 1945) to fifth generation
computers (now and the future)
• Each new generation is characterized by a
major technological development
Computer History (cont’d)
• The first calculating device, which was used 2000
years ago was called abacus
• In 1833, Prof. Charles Babbage, the father of
computer, developed a machine called analytical
engine which was the base for the modern digital
computer
• Other early computing devices include the slide
rule, the mechanical calculator, and Dr. Herman
Hollerith’s Punch Card Tabulating Machine and
Sorter
Computer History (cont’d)
• First - Generation Computers
(approximately 1946 - 1957)
– The electronic digital computers, which were
introduced in 1950's, were using vacuum tubes
– ENIAC
• Was developed during World War II
– UNIVAC
• Released in 1951
Computer History (cont’d)
• Second - Generation Computers
(approximately 1958 - 1963)
– used transistors
• A small device made of semiconductor material
– Programming languages (FORTRAN and
COBOL) were developed and implemented
– Computers used by military, government and
big business
Computer History (cont’d)
• Third - Generation Computers
(approximately 1964 - 1970)
– Introduction of integrated circuits (ICs)
• Also know as chips
– Keyboards and monitors were introduced for
input and output
– Magnetic disks were typically used for storage
– Cheap, fast and reliable
– Used by small business
Computer History (cont’d)
• Fourth - Generation Computers (approximately
1971 - present)
– The invention of the microprocessor in 1971
• Contains the core processing capabilities of an entire computer
on one single chip
• Example: IBM PC and Apple Macintosh
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Input - keyboard and mouse
Output – monitor and printer
Storage – magnetic disks and optical disks
The development of computer network, wireless
technologies, and the internet
Computer History (cont’d)
• Fifth - Generation Computers (now and the
future)
– Will be based on artificial intelligence
• Computers can learn, think and reasoning
– Voice recognition
• Become primary means of input
– Optical computers
• Process data using light instead of electrons
Computer History (cont’d)
1.5 Computer Applications in
Society
Computer Applications in
Society
Some examples of computer
applications in society:
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Education
Finance
Government
Healthcare
Science
Publishing
Travel
Manufacturing
Review
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Computer definition?
Computer operations?
Computer main components?
Computer categories?
Computer impacts on society?
For more details information and pictures, please refer to your text book.