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CUIT 111: COMPUTER APPLICATIONS FOR ENGINEERS
INSTRUCTOR: P.MASTARA
CHAPTER 1:
INTRODUCTION / IT Overview
CONTENTS
CHAPTER 1: Types of computers
• Mainframe
• Minicomputer
• Micro Computer
• Super Computer
CHAPTER 2: Basic components
of a computer
• Firmware
• Hardware
• Software
• Computer Aided Design /
Manufacturing
CHAPTER 3: Networks
• Basic elements
•Types
of networks
•Network terminology
CHAPTER 4: The Internet
•WWW
•Search engines
•Web browsers
•Common internet terminology
•Internet security strategies
•Communication on the internet
•Education on the internet
CHAPTER 5: Operating
Systems
•Windows XP
CHAPTER 1: TYPES OF COMPUTERS
Different types of computers are used for different
tasks. It is important to understand the differences
between computer systems in order to select an
appropriate technology for a particular function
 Based upon relative size and function, computers can
be classified as follows:

MAINFRAME COMPUTERS






A mainframe is a large, powerful computer capable of
serving a large number of users at the same time.
Users connect to it using another smaller computer (or
Dumb terminal) which consists simply of a keyboard and
screen to enter and display information. A dumb terminal
does not process or store any data itself.
Because mainframes need to process and store information
for many different users at once, they require much more
processing power and storage capacity than other
computers, i.e. they need to be faster and have more
memory.
Very expensive.
Processing capacity measured in Millions of Instructions
per Second(MIPS)
An automatic cash dispenser at a bank is an example of a
dumb terminal connected to the mainframe via a network.
MINICOMPUTER
A Minicomputer is smaller, less powerful version of a
mainframe.
 Lower processing power and storage capacity mean that a
minicomputer is cheaper than a mainframe but is not able
to serve as many users at once.
 As with a mainframe, users do not sit down in front of the
minicomputer itself. They connect to it using another
smaller computer or a dumb terminal.
 Minicomputers are often used by medium-sized companies
or departments in larger organizations, to provide a
centralized store of information and computer programs
e.g. database server or web server)

MICROCOMPUTER
An example is a desktop computer.
 The “Personal Computer” or PC is a microcomputer.
 The PC is the most common type of computer used in
offices and at home.
 Usually, only one user accesses a microcomputer at a
time.
 Other examples are palmtop and laptop
 The user sits in front of the microcomputer and works
with it directly, rather than connecting to it using
another computer.
 It requires far less processing power and storage
capacity than either a mainframe or a minicomputer.
This in turn means that microcomputers are much
cheaper.

SUPER COMPUTER
A computer which has the highest computation rate,
largest memory, or highest cost.
 It is the fastest, most powerful, and most expensive
computer used for applications that require complex
and sophisticated mathematical calculations.
 E.g. NASA’S Columbia for simulation of the earth’s
evolution and planetary ecosystems.
 Processing power measured in FLOPS (Floating Point
Operations Per Second).

QUESTION
Question 1:
Describe the 5 computer generations based on the
following:
 Hardware
 Software
 Computing characteristics
 Physical appearance, and
 Applications.
QUESTION 2
Identify a suitable type of computer to perform the
following tasks(Justify your answer):
a)
b)
c)
d)
e)
f)
g)
Make a sales presentation at a client's office, using business
graphics software.
Create a company newsletter
Store a sales database for six regional offices worldwide
Perform Fluid Dynamics Calculations
Perform Simulation and modeling of the galaxy’s systems
Host account information processing and storage for a mobile
network service provider
Maintain a student database for a university.
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CHAPTER 2:
BASIC COMPONENTS OF A COMPUTER
BASIC DEFINITIONS

Information Technology (IT): Refers to all the procedures
and equipment used by people to improve the quality of
gathering, processing, communicating and storing
information.
Question: What is the difference between I.T and I.C.T?


Data: Raw facts, figures, transactions etc which have been
recorded.
They are facts obtained by reading, observation, counting,
measuring, weighing etc
Information: Data that has been processed in such a way
as to be useful to the recipient. Information can be Words,
numbers, pictures, sound or video
1. FIRMWARE:
A software program or set of instructions programmed on a
hardware device.
Typically contained in computer components such as ROM,
PROM, hard disks and keyboards.
Often referred to as a combination of software and hardware
A day-to-day example is a remote control
2. HARDWARE:
The collection of physical elements that comprise a
computer system.
 Computer hardware refers to the physical parts or
components of computer such as monitor, keyboard, hard
disk, mouse, etc.
 Refers to objects that you can actually touch, like disks,
disk drives, display screens, keyboards, printers, boards,
and chips

HARDWARE CONT….
Hardware Components
 A block diagram of the basic setup of a typical computer
system appears in Figure below:

The major components are as follows:
A)


CPU
Is the central processing unit, often called simply the processor,
where the actual execution of a program takes place.
3 Major Components:
i. ALU (arithmetic logic unit)

Performs calculations and comparisons (data changed)
ii. CU (control unit):

Functions:
Moves data to and from CPU registers and other hardware components
(no change in data)
 Accesses program instructions and issues commands to the ALU


Subparts:
Memory management unit: supervises fetching instructions and data
 I/O Interface: sometimes combined with memory management unit as
Bust Interface Unit


Registers

Small, permanent storage locations within the CPU used for a
particular purpose

Can hold data, an address or an instruction
B).
MEMORY
A program’s data and machine instructions are stored
here during the time the program is executing. Memory
consists of cells called words, each of which is
identifiable by its address.
 Read Operation: If the CPU fetches the contents of
some word of memory.
 Write operation: If the CPU stores a value into some
word of memory.

MEMORY(CONT….)
Ordinary memory is called RAM, for Random Access
Memory, a term which means that the access time is the
same for each word.1
 ROM (Read-Only Memory) is memory which can only be
read but not written. Used for programs which need to be
stored permanently in memory, staying there even after the
power is turned off. For example, an autofocus camera
typically has a computer in it, which runs only one program,
a program to control the operation of the camera.

MEMORY MEASUREMENT
The smallest usable unit of measure for memory is the byte
– the amount of memory required to hold one character, like
the letter A or the numeral 2.
 1 byte is equivalent to 8 bits(or 1s and 0s), which is the most
basic unit of data in a computer.
 Computers work with larger chunks of data, measured in
multiple bytes, as below:

Unit
Approx. Value (bytes)
Actual Value (bytes)
Kilobyte (KB)
1,000
1,024
Megabyte (MB)
1,000,000
1,048,576
Gigabyte (GB)
1,000,000,000
1,073,741,824
Terabyte (TB)
1,000,000,000,000
1,099,511,627,776
C)
I/O DEVICES
A typical computer system will have several
input/output devices, typical examples being
keyboards/monitor screens, floppy and fixed disks,
CDROMs, modems, printers, mice and so on.
 They serve as interfaces between the computer and the
“outside world.” In all cases, they are communicating
with a program which is running on the computer.

D)
SYSTEM BUS
A set of parallel wires (usually referred to as “lines”),
used for communication between components. The CPU
communicates with memory and I/O devices via the bus.
 It is also possible for I/O devices to communicate directly
with memory, an action which is called direct memory
access (DMA), and again this is done through the bus.
 They can also be referred to as the electronic highway on
which data travels within a computer, from one
component to another.
 Basically, it's the conduit used by your entire system to
communicate with your CPU.
 The bus is a collection of wires and connectors through
which the data is transmitted. All buses consist of two
parts -- an address bus and a data bus.

Data Bus:
 This is used for sending data. When the CPU reads a
memory word, the memory sends the contents of that
word along the data bus to the CPU; when the CPU
writes a value to a memory word, the value flows along
the data bus in the opposite direction.
 Since the word is the basic unit of memory, a data bus
usually has as many lines as there are bits in a memory
word. For instance, a machine with 32-bit word size
would have a data bus consisting of 32 lines.
Address Bus:
 When the CPU wants to read or write a certain word of
memory, it needs to have some mechanism with which to tell
memory which word it wants to read or write. This is the role
of the address bus.
 For example, if the CPU wants to read Word 504 of memory,
it will put the value 504 on the address bus, along which it
will flow to the memory, thus informing memory that Word
504 is the word the CPU wants.
 The address bus usually has the same number of lines as
there are bits in the computer’s addresses.
Control Bus:
 To alert the memory when the CPU wants to
read or write. This is one of the functions of the
control bus. For example, the control bus in
typical PCs includes lines named MEMR and
MEMW, for “memory read” and “memory write.”
If the CPU wants to read memory, it will assert
the MEMR line, by putting a low voltage on it,
while for a write, it will assert MEMW. Again,
this signal will be noticed by the memory, since it
too is connected to the control bus, and so it can
act accordingly.
The Motherboard
A motherboard (or system board) is a large
printed circuit board which connects together all
the components in the computer.
 Allows the components to exchange data.
 The type of motherboard determines the types of
CPU, memory and hard disk that can be installed
in the computer.

3. SOFTWARE
The programs and other operating information used by a
computer.
 A generic term for organized collections of computer
data and instructions
 The programs used to direct the operation of a
computer, as well as documentation giving instructions
on how to use them.

SOFTWARE
i.
System software:
a) Operating System Software
DOS, Windows XP, Windows Vista, Unix/Linux, MAC/OS
X etc.
b) Utility Software
Windows Explorer (File/Folder Management), Windows
Media Player, Disk Defragmentation, Disk Clean,
BackUp, etc…
ii. Application software:
a) Package Software:
i.e. – Off-The-Shelf software
Ms. Office 2003, Ms. Office 2007, Macromedia (Dreamweaver,
Flash, Freehand), Adobe (PageMaker, Photoshop)
b) Tailored or Custom Software:
SAGE (Accounting).
Examples of application software including:
 Word Processing Software: Software that enables
users to create and edit documents.
e.g. MS-Word, WordPad, Notepad.

Database Software: A database is a structured
collection of data. Allows the users to store and retrieve
data from databases. E.gs Oracle, MS Access



Spreadsheet Software: Organises data and allows users
to perform calculations.
They simulate paper worksheets
by displaying multiple cells that make up a grid.e.gs Excel,
Lotus 1-2-3 and Apple Numbers.
Multimedia Software: Allows users to create and play
audio and video media.
Audio converters, players, burners, video encoders and
decoders are some forms of multimedia software.e.gs Real
Player and Windows Media Player.
Presentation Software:
The software that is used to display information in the form
of a slide show. e.g. Microsoft PowerPoint.
TASK: CLASSIFY THE FOLLOWING EXAMPLES OF
SOFTWARE
i.
ii.
iii.
iv.
v.
vi.
vii.
viii.
ix.
x.
Microsoft Access
Microsoft Project
Microsoft Excel
Microsoft Word
Microsoft Office Publisher
Microsoft Office Powerpoint
Microsoft Office Outlook
Windows Media Player
Microsoft Office picture manager
Skype
III.
COMPUTER PROGRAMMING LANGUAGES:
An artificial language designed to communicate
instructions to a machine, particularly a computer.
 Programming languages can be used to create programs
that control the behavior of a machine and/or to express
algorithms precisely.

What is a program?

A program is something that is produced using a
programming Language.
What is a Programming Language?

A programming Language is a notational system
intended primarily to facilitate human-machine
interaction.
LEVELS/GENERATIONS OF PROGRAMMING
LANGUAGES
 1st Generation Programming language (1GL)
 Machine Language: 0s or 1s
 The lowest level of language.
 The instructions in 1GL are made of binary
numbers, represented by 1s and 0s.
 2nd Generation Programming language (2GL)
 Assembly Language : Mnemonics
 The language is specific to a particular processor
family and environment.
Find:
The differences between 1st and 2nd generation
languages
 3rd
Generation Programming language (3GL)
 High-Level Languages ; (procedure oriented or
Object Oriented)
 Translator for High-level languages is either a
Compiler or an Interpreter.

Examples of High-level languages:
FORTRON
― COBOL
― BASIC
― C and C++
―
 4th
Generation Programming language (4GL)
 Very-High-Level Languages


consist of report generators, query languages, application
generators, and interactive database management system
For example:
 RPG III (Report Generator)
 SQL (Structured Query Language)
 NOMAD and FOCUS (DBMS)
 5th
Generation Programming Language
 Natural Languages: Are designed to make the
computer solve a given problem without the programmer.

Natural languages are part of the field of study known as
Artificial Intelligence
COMPUTER AIDED MANUFACTURING
The use of computer software to control machine
tools and related machinery in the manufacturing of
workpieces.
 A factory can become highly automated, through systems
such as real-time control and robotics.
 A CAM system usually seeks to control the production
process through varying degrees of automation.
 Combined with a CAD system, the resulting integrated
CAD/CAM system takes the computer-generated design,
and feeds it directly into the manufacturing system; the
design is then converted into multiple computercontrolled processes, such as drilling or turning.

COMPUTER AIDED DESIGN
Use of computer systems to assist in the creation,
modification, analysis, or optimization of a design
communications through documentation, and to create
a database for manufacturing.
 Used for the accurate creation of photo simulations
 Without which it would be time consuming, labourintensive and costly process

Advantages
 Because each of the many manufacturing processes in a
CAM system is computer controlled, a high degree of
precision can be achieved that is not possible with a
human interface.
 Another advantage of Computer Aided Manufacturing is
that it can be used to facilitate mass customization: the
process of creating small batches of products that are
custom designed to suit each particular client.
 Without CAM, and the CAD process that precedes it,
customization would be a time-consuming, manual and
costly process.
 However, CAD software allows for easy customization
and rapid design changes: the automatic controls of the
CAM system make it possible to adjust the machinery
automatically for each different order.
CAE
The broad usage of computer
software to aid in engineering
tasks.
 It includes computer-aided design (CAD),computeraided analysis (CAA),computer-aided
manufacturing (CAM) and computer-aided
planning (CAP)
 CAE tools are very widely used in the automotive
industry and aerospace.

RELATED SOFTWARE
AUTOCAD: an interactive drawing system designed to
permit a user to construct or edit a drawing on a graphics
display.
 AutoCAD is used in field of architectural and mechanical
designing, mapping and 3D.

APPLICATION OF IT IN CIVIL ENGINEERING
 The
application of planning, designing,
constructing, maintaining, calculations,
including structural design, geometry
calculations, and applications for project
management.
APPLICATION OF IT IN ELECTRONIC
ENGINEERING
A
broad scientific and profound knowledge
of electronic circuits and systems
knowledge of telecommunications and
computer-controlled systems.
APPLICATION OF IT IN
CHEMICAL
ENGINEERING
 Advancements
in computer science found
applications designing and managing plants,
simplifying calculations and drawings,that
previously had to be done manually.
 Engineering work processes is an emerging and
challenging area of research and development.
 Supporting the activities during the life cycle of a
chemical process by means of information
technology. Emphasis will be largely on the
process and plant design process
Modeling, numerical analysis and simulation
• Informatics and intelligent systems
• Process and product synthesis/design
• Process control and monitoring
• Events management and process safety
• Plant operations, integration, planning/
scheduling and supply chain.
Global chemical industry by focusing on
advancements of information
technology and business
management skills.
Advantage of the speed of computer analysis, the
engineer can explore a greater number of design options
in a short period of time.It allows an engineer to make
immediate comparisons and see the impact of each.
 We can develop structural behaviour from a single
project rather than having to await the accumulative
experience of several projects.

CHAPTER 3: NETWORKS
What is a data network?
A group of computers and devices interconnected by
communications channels that facilitate communications
among users and allows users to share resources.
1. BASIC ELEMENTS OF A NETWORK
Data/information networks vary in size and capabilities,
but all have four basic elements in common:
 Protocols: Rules or agreements to govern how the
messages are sent, directed, received and interpreted.
 The messages or units of information that travel from
one device to another
 A means of interconnecting these devices - a medium
that can transport the messages from one device to
another
 Devices on the network that exchange messages with
each other

MEDIUM
It interconnects the devices.
 It is either copper (electrical signals), optical fiber (light
signals) or microwave (wireless) signals.
 Examples of copper medium are coaxial cable and TP
cable.
 Examples of microwave signals are satellite signal
transmission between a device on earth and a satellite
in orbit.

PROTOCOLS
People often wish to send and receive a message using
computer applications and these applications require
services be provided by the network.
 Some of these services include the World Wide Web, email, instant messaging, and IP Telephony. Devices
interconnected by medium to provide services must be
governed by rules, or protocols.
 Protocols are the rules that the networked devices use to
communicate with each other. The industry standard in
networking today is a set of protocols called TCP/IP
(Transmission Control Protocol/Internet Protocol).
TCP/IP is used in home and business networks, as well as
being the primary protocol of the Internet.

e.gs
Service
WWW(World Wide Web)
e-mail
Protocol
HTTP
SMTP or POP
MESSAGES
For it to travel from one node to the next it has to be
converted into a format that is compatible with the
medium.
 All types of messages must be converted to bits, binary
coded digital signals, before being sent to their
destinations.

NETWORK INFRASTRUCTURE
The network topology defines the way in which the nodes
of a local area network (LAN) or a wide area network
(WAN) are connected to each other.
 These connections involve equipment like routers,
switches, bridges and hubs using cables / medium
(copper, fiber, and so on) or wireless technologies (Wi-Fi).

2. TYPES OF NETWORKS
LAN
This is a network which only connects together computers
in the same building/site e.g. office or building or
university campus.
 Each computer on a network is called a workstation or
terminal
 If the workstation has processing ability it is known as an
Intelligent Terminal otherwise Dumb Terminal.
MAN
A network that interconnects users with computer
resources in a geographic area or region larger than that
covered by a local area network (LAN) but smaller than the
area covered by a wide area network (WAN)
 Usually designed for a town or city.

WAN
Connects computers in different geographical locations.
 For example computers in a Harare office connected to
the organization's Chinhoyi offices.
 Two or more LANs or MANs can be connected together
to form a Wide Area Network.


Advantages
Networking allows users to share resources
including files and programs, printers or modems
and share the Internet connection as well.
 People can also communicate over a network
using programs such as Google Talk, Skype or
Microsoft Outlook.

NETWORK TERMINOLOGY
i. Server:
 A computer or computer program that manages access to a
centralized resource or service in a network.
 There are many different types of servers, including the
following:
Mail Servers - They move and store mail over corporate
networks via LANs and WANs and across the Internet.
 Proxy Server - Proxy servers sit between a client
program typically a Web browser and an external server
(typically another server on the Web) to filter requests,
improve performance, and share connections
 Web Servers - Serves static content to a Web browser by
loading a file from a disk and serving it across the
network to a user's Web browser. The browser and server
talking to each other using HTTP mediate this entire
exchange.
 Application server - A server dedicated to running
certain software applications
 Database server - Provides database services to other
computer programs or computers

ii. Modem:



MOdulator-DEModulator.
It is a device that translates digital (machine) signals to analogue (signals
carried by the media) and vice versa.
This means it understands both the languages of the computer and the
telephone.
iii. E-mail:






This is the transmission of written messages by electronic means via a
computer network.
Each user of the e-mail has an e-mail address to which messages are sent.
The messages can be notes entered from the keyboard or electronic files and
a message can take a few seconds to arrive.
The recipient of the message does not have to be on-line when the message
is sent and he can see the message whenever he accesses his message store
or mailbox.
Hence e-mail systems are based on a store and forward model.
You can get a free e-mail address from web-sites such as www.yahoo.com,
www.hotmail.com and www.google.com
iv. Intranet
 Internal or private network of an organization based on
internet technology (such as hypertext and TCP/IP
protocols) and accessed over the internet.
 It is meant for the exclusive use of the organization and
its associates (customers, employees, members,
suppliers, etc.) and is protected from unauthorized
access with security systems such as firewalls.
 Intranets provide services such as email, data storage,
and search and retrieval functions, and are employed
in disseminating policy manuals and internal
directories for the employees, price and product
information for the customers, and requirements and
specifications for the suppliers.
 Some intranets are confined to a building whereas
others span continents.
v. Extranet
 Part of a company’s intranet that is extended to users
outside the company, normally over the internet. They
provide suppliers, vendors, and customers limited
access to corporate data to check order status,
inventory, and parts lists.
QUESTION:

State the similarities and differences between an
intranet and an extranet.
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CHAPTER 4:
THE INTERNET
DEFINITION
This is a huge international network made up of
smaller networks that are linked together like a spider
web.
 It is a wide area network that covers a wide
geographical area.
 In other words it is a combined collection of academic,
commercial, government and private networks
connected over international telecommunication
backbones and routed using IP addressing.
 Activities that are facilitated by the internet include
communication, education, commerce, entertainment,
collaboration, data transfer and commerce.

WORLD WIDE WEB
A term often confused with the internet. Also known as
the web.
 The difference is that the internet is the term referring
to the physical connection of the world-wide network
whilst the WWW holds all the information which moves
around the Internet.
 It can be defined as a system of interlinked hypertext
documents/web pages contained on the Internet.
Contains web pages that may contain text, images,
videos, and other multimedia and one can access them
by using hyperlinks.

SEARCH ENGINES
These are WEB SITES that enable users to query
an index and then return results relevant to the
query.
 You can search by typing the concept, keyword,
site and/ links.
 After searching the search engine will display the
results and the user can select the appropriate site.
 Examples include

www.bing.com,
 www.ask.com,
 www.google.co.zw

WEB BROWSERS
COMPUTER PROGRAMS (such as Internet Explorer
or Mozilla Firefox) that enables internet users to access,
navigate, and search World Wide Web sites.
 Browsers interpret hypertext links and allow
documents formatted in hypertext markup language
(HTML) to be viewed on the computer screen, and
provide many other services including email and
downloading and uploading of data, audio, and video
files.

MOZILLA FIREFOX
Search Box
Browser tabs
Windows Start Button
Mail log-in option
Web Site address
COMMON INTERNET TERMINOLOGY




Chat Rooms
A facility that enables two or more people to engage in interactive
“conversations” over the Internet.
Newsgroups
Online discussion groups that focus on specific topics
Web log(Blog)
A blog is a web site that people can create and use to write about their
observations, experiences and feelings on a wide range of topics.
Wiki
A wiki is a collaborative Web site that allows users to create, add to,
modify, or delete the Web site content via their Web browser. Many
wikis are open to modification by the general public. Wikis usually
collect recent edits on a Web page so that someone can review them for
accuracy. The difference between a wiki and a blog is that users
cannot modify original posts made by the blogger.
VIRUSES, WORMS AND TROJANS

Viruses - programs that attach to files or applications and
can travel from one computer to the next when unknowingly
opened by a human

Worms – these can travel like viruses but do not need human
interaction to do so

Trojan horses – these appear to be helpful software but
when opened cause problems and can even create a security
hole through which other hackers can enter the computer or
network.
SECURITY STRATEGIES



Prevention: Security guidelines, advisories, common sense
Detection: Monitor webserver logs, system activity,
detection software
Response: Script-level, webserver, institutional policies
CLIENT-SIDE THREATS
Content spoofing: tricks a user into believing content is
from a different website (e.g. using redirection).
 Cross-site scripting (XSS): forces a website to display
malicious code in a user’s browser.
 Phishing: masquerading as a trustworthy website in order
to obtain user’s passwords, bank details etc.
 Spam: unwanted email. Hacker abuses script that sends
emails to unchecked addresses entered via a web form.

COMMUNICATION ON THE INTERNET
The internet was designed as a means of communication by
the United States army.
 Communication over the internet has evolved, and it makes
use of communication channels such as:
 E-mail
 Instant Chat
 Video Conferencing
 Voice
 Chat rooms, newsgroups, blogs, e.t.c
 Web pages


Communication over the internet is governed by a set of
protocols, which describes a set of rules, according
to which the communication between two or more parties
must be performed.
A)
E-MAIL
Advantages
 Speedy delivery. They are delivered at once around the
world.
 Advanced services such as automated delivery, message
prioritization.
 Compatible with many media types
 Cheap
 Easy to reference
 Global access
Disadvantages
 Lack of personal touch
 Security threat- viruses, e.t.c
 Spam
 Possibility of loss of mail in the case of mailbox flooding and
network malfunction
E-MAIL CONT….
It uses protocols such as SMTP and FTP
 Client software applications that support e-mail are
Microsoft Office Outlook or Outlook express.
 Supports text but other file formats such as music and
video files or pictures can be attached to the e-mail and
sent with the e-mail.
 Web sites:

B) INSTANT
CHAT
A form of online communication that allows real-time (or
close to real-time) interaction through personal
computers or mobile computing devices.
 Users can exchange messages privately, similar to email, or join group conversations.
 Apart from typed text, it supports media formats such
as images, audio and video files, and other attachments
 Supported by applications such as G-Talk, WhatsApp
and IM Messenger
 Service provided by companies such as Google and
Microsoft

IC ADVANTAGES AND DISADVANTAGES
Advantages


Instant message delivery and real time response
Is compatible with smaller technologies such as mobile phones, improving
reach

Not limited by location of participants

It allows creation of virtual conferences

Advanced services such as storage of conversations

(Limited)Support for other media types

Cheap

Easy to use

Global reach
Disadvantages

Absence of the personal touch-emotional bias

Authentication of chat peers is not definite

Security threat-viruses

Possibility of misuse in companies

Possibility of interception of communication

Can be a distraction in other activities
C)
VIDEO CONFERENCING
Communication among people at remote locations by
means of transmitted audio and video signals
 At the most basic level, it is supported by applications
such as Skype and video calls such as supported by 3G
telephone networks
 Supports Telepresence, Group video conferencing,
desktop/ personal video conferencing, e.t.c
 Makes use of protocols such as RTP.
 Supports video, audio and data.

VIDEO CONFERENCING ADVANTAGES AND DISADVANTAGES
Travel reduction
 Global reach
 Closely resembles a direct personal conversation
 Improved interaction: PowerPoint and other visual
displays can be shared with everyone attending the
conference at the same time, giving the feel of everyone
being in one room and keeping everyone on task and
focused.
Improved collaboration, allows many people to be
involved at once
 Video communications enables data, documents and
images to be shared instantly.
 Immediate reach
 Advanced services such as virtual whiteboards

DISADVANTAGES

Cost
Initial set-up costs: Equipment, software, maintenance
Operating costs: Network bandwidth
Not perfectly able to replace physical presence
 Usability

D)
IP TELEPHONY
It is supported by a protocol called Voice over Internet
Protocol(VoIP)
 It is a method for taking analog audio signals, and
turning them into digital data that can be transmitted
over the Internet.
 It refers to communication protocols, technologies,
methodologies, and transmission techniques involved in
the delivery of voice communications and multimedia
sessions over Internet Protocol (IP) networks, such as
the Internet.
 Supported by protocols such as Skype

ADVANTAGES
Bandwidth efficiency
 Cost saving
 Global reach
 Portable(virtual) number
 Extra services such as support for video calls

DISADVANTAGES
 Origin of phone call can be untraceable
 Affected by power outages
 Reliance on the internet network
 Voice quality can be poor
 Security: Viruses, spamming, DoS and phishing attacks
EDUCATION
Research
 Collaboration
 Distance learning
 Technology-enhanced learning

Collaboration: The action of working with one or more
other people to produce or create something.
Tool: A device or implement, especially one held in the
hand, used to carry out a particular function.
e.gs – Video Calls(Skype), Cloud based Services(Google Docs,
Google Drive), Wikis(Wikipedia), Chat apps(IM), Ambient
communications(Twitter), Image sharing(Flickr),
Specialized apps(Google earth), E-learning apps(moodle)
GOOGLE DOCS
A free web-based office suite offered by Google within its
Google Drive service.
 It allows users to create and edit documents online while
collaborating in real-time with other users.

Google Drive is a file storage and synchronization service.
It enables user cloud storage, file sharing and collaborative
editing.
Files shared publicly on Google Drive can be searched with
engines like Open Drive
A good tool should
 Promote communication;
 Share a diagram, photograph, paper, or similar
objects;
 Allow natural interactions; and
 Be easy to use and learn.
OPERATING SYSTEM
WINDOWS XP
CHAPTER 5
DEFINITION
An OS is a program which acts as an interface between
computer system users and the computer hardware.
 It provides a user-friendly environment in which a user
may easily develop and execute programs.
 Otherwise, hardware knowledge would be mandatory for
computer programming.
 So, it can be said that an OS hides the complexity of
hardware from uninterested users.


In general, a computer system has some resources which
may be utilized to solve a problem. They are
Memory
 Processor(s)
 I/O
 File System

e.t.c



The OS manages these resources and allocates them to
specific programs and users.
With the management of the OS, a programmer is rid of
difficult hardware considerations.
An OS provides services for






Processor Management
Memory Management
File Management
Device Management
Concurrency Control
It is used as a predefined library for hardware-software
interaction.
COMPUTER SYSTEM RESOURCE
FRAMEWORK
Application Programs
System Programs
Operating System
Machine Language
HARDWARE
EVOLUTION
The first computers did not use the mouse. It was
popular as standard equipment with the Apple
Macintosh.
 It became even more popular with the growth in
popularity of the Graphical User Interface

THE WINDOWS O.S PLATFORM
To date, WINDOWS has developed many Operating
Systems, including Windows XP and Windows 7.
 Other examples of operating systems not developed by
Windows include Ubuntu and MAC OS which is popular
on Apple computers.
 Windows gained popularity as it’s design focused on the
user population which was using the personal computers.
 The introduction of the mouse corresponded to the
introduction of the Icon and a Graphical User Interface,
allowing a user to implement a command by simply
clicking on an Icon

DESKTOP
Icon
Recycle bin
Desktop
Task Bar
Start Button
System Tray
TASK
Give an example of each of the following Operating
system types, highlighting its unique features:
i.
Open Source
ii.
Server
iii. Mobile phone
iv. Windows

DESKTOP ICONS
 Recycle
Bin: Contains the documents and files
that have been deleted. It needs to be emptied to
permanently lose the data that it holds.
 Desktop: The area of screen that provides the
Graphical User Interface containing icons and
shortcuts.
 Wallpaper: The picture on the background that
fills the Desktop area.
 Icons: Shortcuts used to provide quick access to
files and folders such as My Documents folder
and also for launching programs.
START BUTTON
When pressed it gives a
list of the programs
installed on the computer
as shown below
SHORTCUT FOR DOCUMENT
Right Click on the Desk Top
 Click on New
 Click on Shortcut
 Click on browse to specify the location of the document
you desire to access. For example, if it is a document in
the My Documents folder, you browse to My Documents
and select the document.
 Click on Ok and then Click on Next
 Specify a name to use for the document
 Click on Finish

CREATING AN ICON ON DESKTOP
 To
add an Icon:
 Click on the Start button.
 Put your mouse over All Programs. A menu
will appear with all of your programs.
 Go to the program that you want to create a
shortcut for and Right-click on it. A menu will
appear.
 Click on Send to then Desktop Create
Shortcut.
 Left-click on the desktop area to see your new
icon.
CREATING A DESKTOP ICON CONT…
 To add an Icon:
 Click on the Start button.
 Put your mouse over All
Programs. A menu will appear
with all of your programs.
 Go to the program that you
want to create a shortcut for
and Right-click on it. A menu
will appear.
 Click on Send to then Desktop
Create Shortcut.
 Left-click on the desktop area
to see your new icon.
CONTROL PANEL
To get access to the Control Panel:
 Click on Start then click Click on Control Panel
 It contains specialized tools that are used to
change the way the Operating System looks
and behaves. It also provides access to
administrative tasks such as:
 Appearance and Themes, Network and
Internet Connections, Printers and other
hardware, Performance and Maintenance, User
Accounts, Date, Time and language Options
WINDOW
Label
Control Buttons
Address Bar
Page
Links
Information
Scroll Bar
Minimise
Restore
Close
FOLDERS
A virtual container in which groups of computer files or other
folders can be kept and organized.
 Files can be organized by keeping related documents within
the same folder.
 Sub-Folder: A folder contained inside another folder.
 Some default folders found within the windows user
environment include My Documents, My Music ,My Videos
and My Pictures.
 They are also referred to as directories.

CREATING A NEW FOLDER ON THE DESKTOP
Right click on a blank space on the desktop.
 Scroll to New
 Click on Folder
 Type the name of the folder and press enter

THE KEYBOARD-SHORTCUT KEYS
Close
 Copy
 Cut
 Delete
 Exit
 Find
 Help
 Minimize Window
 Move to Recycling
 New Folder/Document

CTRL+W
CTRL+C
CTRL+X
DEL
ESC
CTRL+F3
F1
Windows Key*+M
CTRL+DEL
CTRL+N
THE KEYBOARD-SHORTCUT KEYS CONT…
Open
 Open Start Menu
 Paste
 Page Up/Down
 Print
 Print Screen
 Quit
 Reboot/Restart
 Save
 Select All
 Undo

CTRL+O
Windows Key*
CTRL+V
Page Up/Down Keys
CTRL+P
ALT+Print Screen Key
ALT+F4
CTRL+ALT+DEL
CTRL+S
CTRL+A
CTRL+Z