lesson_1_Introduction_to_computers_pptx.pptx

Sanjeev Kumar
shivaysanjeev@gmail.com
1
CHAPTER 1:
Introducing Computer Systems
Introduction to Computers

Preview and Objectives
2
 Identify the various parts of a computer system and what each does.
 Identify various Operating Systems.
 Identify major software applications packages and what they do.
 Know how to use common features of windows and the desktop.
 Know how to organize files and folders usingWindows Explorer.
 Be familiar with features common toWindows software.
 Have a working knowledge of Microsoft Office software.
 Use computers in the business workplace and other fields.
 Explain why Information Systems are so important today and how they are transforming
organizations and management
 Identify appropriate goals and objectives for organizations.
 Use various positioning frameworks to analyze an organization’s dependence on
Information systems.
 Produce /devise an Information Systems plan/strategy for an organization.

Definition of a computer
3
 By definition, a computer is an electronic device that inputs
data, processes data(converting it into information that is useful to
people) outputs and stores information.
 Computers are controlled by programmed instructions that
transform the data into meaningful information.
 Generally a Computer is a device that accepts input, processes
it, stores data, and produces output.

Information Processing Cycle
4
 Steps followed to process data
 Input
 Processing
 Output
 Storage

Input
5
 Input: Information provided to the computer by a person, the
environment, or another computer.
Examples of Input
 words and symbols
 numbers
 pictures
 audio signals from a microphone
 signals from another computer
 temperature, speed, pressures, etc. from sensors

Processing
6
 Processing - manipulation of data.
 Data are symbols that represent raw facts, objects, and ideas about
people, places, events, and things that are of importance in an
organization.
 A computer program or software is a series of instructions that
tell a computer how to carry out a processing task.
 Examples of Processing
 Arithmetic calculations
 Sorting a list
 Modifying pictures
 Drawing graphs

Output
7
 Output - the result produced by a computer after processing the
data.
 Output device –displays, prints, or transmits the results after
processing.
 Examples of Output
 images on a monitor
 printed documents
 sounds
 signals to device controllers

Memory and Storage
8
 Memory - the area of a computer that temporarily holds data that
is being processed or waiting to be processed, stored, or output.
 Storage - The area where data can be left on a permanent basis
while it is not needed for processing.
 Examples of Storage
 magnetic disks
 CD-ROM (Compact Disk Read-Only Memory)
 magnetic tapes
 Flash disk
 Memory card
 Floppy disk

Personal and Home Uses of Computers
 Computers allow people with
disabilities to do normal activities.
 Shopping online
 Playing games with other people
 Work from home
 Entertainment such as listening to
music, watching videos etc.
 Enable communication through the
use of (electronic mails) e-mails ,
chats etc.
Introduction to Computers 9

Business Uses of Computers
 Computers allow companies to
keep large amounts of information
at hand.
 Databases
 Makes ordering and tracking
resources quicker and easier.
 Allows people to have meetings
from different locations.
 Helps in information management
which eases the process of decision
making .
 Computers allow people across
the world to communicate easily.

Educational Uses of Computers
 The Internet allows access to
hundreds of online research
materials.
 Allows colleagues to correspond
quickly about ongoing research.
 Eases the process of analysing
research data.

Parts of a Computer System
12
 Computer systems have four parts
 Hardware
 Software
 Data
 User (people)

13
 Computer hardware:
 A computer's hardware consists of electronic devices; the parts you
can see and touch.
 Inotherwords these are tangible parts of a computer.
 The term "device" refers to any piece of hardware used by the
computer, such as a keyboard, monitor, modem, mouse, etc.
 These are mechanical devices that make up the computer.

Computer Hardware Components
 Display Device (Monitor or
LCD screen)
 System Unit
 Floppy disk drive
 CD ROM drive
 Hard disk drive
 Keyboard
 Mouse
14

Other hardware components
 DVD drive (DigitalVersatile Disk)
 CD writer (Compact disk)
 Sound card and speakers
 Modem (Modulate and Demodulate)
 Printers.
15

Peripherals
16
 A peripheral device designates equipment that might be added
to a computer system to enhance its functionality.
 Examples:
 Printer
 Digital camera
 Scanner
 Joystick

17
 Computer Software
 Is the set of instructions that makes the computer perform tasks.
 The software is a part of the computer you cannot touch but is very
important.
 The software is all the programming that makes the computer run;
controlling everything that the computer does.
 For any computer to function, it needs to have software installed on it.

18
 Data:
 Data consists of raw facts, which the computer can manipulate and
process into information that is useful to people.
 Computerized data is digital, meaning that it has been reduced to
digits, or numbers.The computer stores and reads all data as numbers.
 Users:
 People operating the computer.
 Tell the computer what to do.

Essential Computer Hardware
19
 A computer’s hardware devices falls into one of the four categories;
1. Processor
2. Memory
3. Input and Output
4. Storage

20
 Processing Devices
 The procedure that transforms raw data into useful information is
called processing.
 The processor is like the brain of the computer.
 Organizes and carries out instructions from either the user or software.
 Manipulate the data.
 Most computers have several processors.
 Central Processing Unit (CPU) refers to a computer’s processor.

21
 Memory devices
 Memory is made up of one or more sets of chips that Store data or
program instructions either temporarily or permanently. Memory is
divided into two types:
a) Random Access Memory (RAM)
 RAM holds data and program instructions temporarily while the CPU works
with them.
 RAM is volatile, meaning it holds data only when the power is on.When the
power is off, RAM's contents are lost.
 The “random” in RAM implies that any portion of RAM can be accessed at
anytime.This helps make RAM very fast.
 More RAM results in a faster system.

22
b) Read Only Memory (ROM)
 Permanent storage of programs.
 ROM is called non-volatile memory because it never loses its contents.
 Holds instructions that the computer needs to operate.
 Memory is measured in terms of:
 Kilobyte (KB) - 1,000 bytes
 Megabyte (MB) - 1,000,000 bytes
 Gigabyte (GB) - 1,000,000,000 bytes
 Terabyte (TB) - 1,000,000,000,000 bytes.

Position of RAM and ROM on the MotherBoard
23

24
 Input and Output Devices
 Input devices accept data and instructions from the user or from
another computer system.
 Output devices return processed data to the user or to another
computer system.
 Input devices include: keyboard, mouse, scanner, digital camera,
microphone etc.
 Output devices include: monitor, printer, stereo speakers, headphones
etc.
 Communications devices (such as modems and network
interface cards) perform both input and output, allowing computers
to share information.

25
 Storage Devices
 The purpose of storage is to hold data permanently, even when
the computer is turned off.
 Storage devices hold data not currently being used by the CPU.
 Data is commonly stored on a magnetic or optical disk.
 A disk drive is a device that reads data from and writes data
to a disk. Most new computers feature a floppy disk drive, a
hard disk drive, and an optical disk drive.
 The most common optical storage devices are CDROM and
DVD-ROM drives.

Computer Software
26
 Software is a set of instructions that drive a computer to perform
specific tasks.
 These instructions tell the machine’s physical components what to
do.
 A set of instructions is often called a program.
 When a computer is using a particular program, it is said to be
running or executing the program.
 The two most common types of programs are system software
and application software.

Computer Software
27
1) System software: Is any program that controls the computer’s
hardware or that can be used to maintain the computer in some
way so that it runs more efficiently.
 System Software provides a platform for running application
software.
 There are three basic types of system software:
a) An operating system tells the computer how to use its own
components.All computers require an operating system.
 The OS tells the computer how to interact with the user and
its own devices.
 Examples of operating systems includeWindows, Macintosh
operating system and Linux.

Computer Software
28
b) A network operating system allows computers to
communicate and share data across a network while controlling
network operations and overseeing the network’s security.
Example isWindows server 2003.
c) A utility is a program that makes the computer system easier
to use or performs highly specialized functions.
 Utilities are used to manage disks, troubleshoot hardware
problems, and perform other tasks that the operating
system itself may not be able to do. For example a
Symantec antivirus, Partition Magic etc.

Computer Software
29
2) Application Software:Tells the computer how to accomplish
specific tasks, such as word processing or drawing, for the user.
 Some of the major categories of these applications include:
 Word processing software for creating text-based documents
 Spreadsheets for creating numeric-based documents such as budgets.
 Presentation programs for creating and presenting electronic slide
shows.
 Graphics programs for designing illustrations or manipulating
photographs, movies etc.
 Database management software for building and manipulating large
sets of data such as names, addresses etc.

Data and Information
30
 Data are the words, numbers, symbols and graphics that
describe people, events, things, and ideas.
 Data becomes information when it is used as the basis for
initiating some action or for making a decision.
 Information are the words, numbers, and graphics used as the
basis for human actions and decisions.
 A set of data that has been given a name is called a file.
 A file that a user can open and use is called document.
 A folder is a place where groups of computer files and other
folders can be kept and organized.

Files
31
 A file is a named collection of data, stored on a storage medium
such as a hard disk.
 There are two types of files
 Data files contains text, images, or other data that can be used by a
program.
 Executable files contains programs or instructions that tell the
computer how to perform a task.
 Filename extensions describe a file’s contents. For example
Executable files usually end in .exe, word files end in .doc, adobe
acrobat documents end in .pdf etc.

Extensions and Formats
 A filename might be followed by a filename extension that
further describes the file contents.
 Word files end in .doc
 Excel files end in .xls
 The file format is the arrangement of data in a file and the coding
scheme that is used to represent the data.
 The native file format is the format that is saved by the
application that created it.
32

Assignment 1
33
1. Discuss the history and evolution of computers.
(maximum. 3 pages).
2. Computers are used more extensively than ever for tasks
such as banking, investing, shopping and communicating.
Do you see this trend as having a positive or a negative
impact on our society and economy? Give reasons to
support your answer. (maximum. 3 pages).

lesson_1_Introduction_to_computers_pptx.pptx

More Related Content

Similar to lesson_1_Introduction_to_computers_pptx.pptx

Recently uploaded

lesson_1_Introduction_to_computers_pptx.pptx