This PPT is prepared for students and other professionals regarding Management Information System (MIS) subject as lecture notes.This PPT aims to help students to recognize, specify and communicate effectively to data processing personnel to about information system. It also helps students to interpret new developments in information technology and fit into an overall framework. OTHER TOPICS ARE DISCUSSED IN THE CONSECUTIVE PPTs
2. MANAGEMENT
INFORMATION
SYSTEM
P R E PA R E D B Y
T. M A N O J K U M A R
A S S I S T A N T P R O F E S S O R
LECTURE NOTES-UNIT-3
B.Tech,MBA,NET,(Ph.D)
4. Unit-3
Computer: Definition
A computer is a machine that can be programmed to
manipulate symbols. Its principal characteristics are:
It responds to a specific set of instructions in a well-defined
manner.
It can execute a pre-recorded list of instructions (a program).
It can quickly store and retrieve large amounts of data.
7. Unit-3
The operations of computer components are given below:
1) Inputting: It is the process of entering raw data, instructions and
information into the computer. It is performed with the help of input devices.
2) Storing: The computer has primary memory and secondary storage to store
data and instructions. It stores the data before sending it to CPU for processing
and also stores the processed data before displaying it as output.
3) Processing: It is the process of converting the raw data into useful
information. This process is performed by the CPU of the computer. It takes the
raw data from storage, processes it and then sends back the processed data to
storage.
4) Outputting: It is the process of presenting the processed data through
output devices like monitor, printer and speakers.
5) Controlling: This operation is performed by the control unit that is part of
CPU. The control unit ensures that all basic operations are executed in a right
manner and sequence.
Input device enables the user to send data, information, or control signals to a
computer. The Central Processing Unit (CPU) of a computer receives the input
and processes it to produce the output.
9. Unit-3
1) Analogue Computer
Analogue computers are designed to process analogue data.
Analogue data is continuous data that changes continuously
and cannot have discrete values.
They measure the continuous changes in physical quantity
and generally render output as a reading on a dial or scale.
Speedometer and mercury thermometer are examples of
analogue computers
10. Unit-3
Advantages of using analogue computers:
It allows real-time operations and computation at the same
time and continuous representation of all data within the rage
of the analogue machine.
In some applications, it allows performing calculations
without taking the help of transducers for converting the
inputs or outputs to digital electronic form and vice versa.
The programmer can scale the problem for the dynamic range
of the analogue computer. It provides insight into the problem
and helps understand the errors and their effects.
11. Unit-3
2) Digital Computer
Digital computer is designed to perform calculations and logical
operations at high speed.
It accepts the raw data as input in the form of digits or binary
numbers (0 and 1) and processes it with programs stored in its
memory to produce the output.
All modern computers like laptops, desktops including
smartphones that we use at home or office are digital computers.
12. Unit-3
Advantages of digital computers:
It allows you to store a large amount of information and to retrieve
it easily whenever you need it.
You can easily add new features to digital systems more easily.
The cost of hardware is less due to the advancement in the IC
technology.
It offers high speed as the data is processed digitally.
It is highly reliable as it uses error correction codes.
Reproducibility of results is higher as the output is not affected by
noise, temperature, humidity, and other properties of its
components
13. Unit-3
3) Hybrid Computer
Hybrid computer has features of both analogue and digital computers. It
is fast like an analogue computer and has memory and accuracy like
digital computers.
It can process both continuous and discrete data. It accepts analogue
signals and convert them into digital form before processing.
For example, a processor is used in petrol pumps that converts the
measurements of fuel flow into quantity and price. Similarly, they
are used in airplanes, hospitals, and scientific applications.
14. Unit-3
Advantages of using hybrid computers:
Its computing speed is very high due to the all-parallel
configuration of the analogue subsystem.
It produces precise and quick results that are more accurate and
useful.
It has the ability to solve and manage big equation in real-time.
It helps in the on-line data processing.
15. Unit-3
On the basis of size, the computer can be of five types
The first supercomputer was developed by Roger Cray in
1976.
Supercomputers are the biggest and fastest computers.
They are designed to process huge amount of data. A
supercomputer can process trillions of instructions in a
second.
Supercomputers are particularly used in scientific and
engineering applications such as weather forecasting,
scientific simulations and nuclear energy research
16. Unit-3
Characteristics or applications of supercomputers:
It has the ability to decrypt your password to enhance protection
for security reasons.
It produces excellent results in animations.
It is used for virtual testing of nuclear weapons and critical
medical tests.
It can study and understand climate patterns and forecast weather
conditions. It can run in NOAA's system (National Oceanic and
Atmospheric Administration) that can execute any type of simple
and logical data.
It helps in designing the flight simulators for pilots at the beginner
level for their training.
17. Unit-3
2) Mainframe computer
Mainframe computers are designed to support hundreds or
thousands of users simultaneously.
They can support multiple programs at the same time. It
means they can execute different processes simultaneously.
These features of mainframe computers make them ideal for
big organizations like banking and telecom sectors, which
need to manage and process high volume of data.
19. Unit-3
Characteristics of Mainframe Computers:
It can process huge amount of data, e.g. millions of transactions in
a second in the banking sector.
It has a very long life. It can run smoothly for up to 50 years after
proper installation.
It gives excellent performance with large scale memory
management.
It has the ability to share or distribute its workload among other
processors and input/output terminals.
There are fewer chances of error or bugs during processing in
mainframe computers. If any error occurs, it can fix it quickly
without affecting the performance.
20. Unit-3
3) Miniframe or Minicomputer
It is a midsize multiprocessing computer. It consists of two or
more processors and can support 4 to 200 users at one time.
Miniframe computers are used in institutes and departments for
tasks such as billing, accounting and inventory management.
A minicomputer lies between the mainframe and
microcomputer as it is smaller than mainframe but larger than a
microcomputer.
21. Unit-3
Characteristics of miniframe or minicomputer:
It is light weight that makes it easy to carry and fit anywhere.
It is less expensive than mainframe computers.
It is very fast compared to its size.
It remains charged for a long time.
23. Unit-3
4) Workstation
Workstation is a single user computer that is designed for technical
or scientific applications. It has a faster microprocessor, a large
amount of RAM and high speed graphic adapters.
It generally performs a specific job with great expertise;
accordingly, they are of different types such as graphics
workstation, music workstation and engineering design
workstation.
25. Unit-3
Characteristics of workstation computer:
It is a high-performance computer system designed for a
single user for business or professional use.
It has larger storage capacity, better graphics, and more
powerful CPU than a personal computer.
It can handle animation, data analysis, CAD, audio and
video creation and editing.
26. Unit-3
5) Microcomputer
Microcomputer is also known as a personal computer. It is a
general-purpose computer that is designed for individual use.
It has a microprocessor as a central processing unit, memory,
storage area, input unit and output unit.
Laptops and desktop computers are examples of
microcomputers. They are suitable for personal work that may
be making an assignment, watching a movie, or at office for
office work.
27. Unit-3
Characteristics of a microcomputer:
It is the smallest in size among all types of computers.
A limited number of software can be used.
It is designed for personal work and applications. Only one
user can work at a time.
It is less expansive and easy to use.
It does not require the user to have special skills or training to
use it.
28. Unit-3
An input device is essentially a piece of hardware that sends data to a
computer. Most input devices either interact with or control the
computer in some way. The most common input devices are the mouse
and the keyboard, but there are many others.
Some of the popular input devices are:
Keyboard
Mouse
Scanner
Joystick
Light Pen
Digitizer
Microphone
Magnetic Ink Character Recognition (MICR)
Optical Character Reader (OCR)
30. Unit-3
1) Keyboard
The keyboard is a basic input device that is used to enter data
into a computer or any other electronic device by pressing
keys.
It has different sets of keys for letters, numbers, characters,
and functions. Keyboards are connected to a computer through
USB or a Bluetooth device for wireless communication.
34. Unit-3
2) Mouse
The mouse was invented by Douglas C. Engelbart in 1963. Early
mouse had a roller ball integrated as a movement sensor
underneath the device. Modern mouse devices come with optical
technology that controls cursor movements by a visible or invisible
light beam.
A mouse is connected to a computer through different ports
depending on the type of computer and type of a mouse
The mouse is a hand-held input device which is used to move
cursor or pointer across the screen. It is designed to be used on a
flat surface and generally has left and right button and a scroll
wheel between them. Laptop computers come with a touchpad that
works as a mouse.
37. Unit-3
Scanner is an input device, that captures images from the source
which are then converted into a digital form that can be stored on the
disk. These images can be edited before they are printed.
The data or text is written on paper. The paper is feeded to scanner. The
paper written information is converted into electronic format; this format
is stored in the computer. The document will be permanently stored for
the future. The input documents can contain text, handwritten material,
picture extra.
Scanning can be of the black and white or colored picture. On stored
picture 2D or 3D rotations, scaling and other operations can be applied.
38. Unit-3
A scanner is connected to a computer through USB.
There are different types of scanners:
Flatbed scanner – uses a flat surface to scan documents
Sheetfed scanner – like a laser printer where paper is fed
into the scanner
Handheld scanner – the scanner is dragged over the page to
be scanned
Card scanner – for scanning business card
39. Unit-3
Joystick
Joystick is a input device. It also a pointing device, which is
used to move the cursor position on a monitor screen. It is a
stick having a spherical ball at its both lower and upper ends.
The lower spherical ball moves in a socket. The joystick can be
moved in all four directions.
The function of the joystick is similar to that of a mouse. It is
mainly used in Computer Aided Designing (CAD) and playing
computer games
40. Magnetic Ink Card Reader (MICR)
MICR input device is generally used in banks as there are
large number of cheques to be processed every day. The bank's
code number and cheque number are printed on the cheques
with a special type of ink that contains particles of magnetic
material that are machine readable.
This reading process is called Magnetic Ink Character
Recognition (MICR). The main advantages of MICR is that it
is fast and less error prone.
41. Unit-3
Optical Character Reader (OCR)
OCR is an input device used to read a printed text.
OCR scans the text optically, character by character, converts
them into a machine readable code, and stores the text on the
system memo
42. Unit-3
Bar Code Readers
Bar Code Reader is a device used for reading bar coded data
(data in the form of light and dark lines). Bar coded data is
generally used in labelling goods, numbering the books, etc. It
may be a handheld scanner or may be embedded in a
stationary scanner.
Bar Code Reader scans a bar code image, converts it into an
alphanumeric value, which is then fed to the computer that
the bar code reader is connected to.
43. Unit-3
Optical Mark Reader (OMR)
OMR is a special type of optical scanner used to recognize the
type of mark made by pen or pencil. It is used where one out of
a few alternatives is to be selected and marked.
It is specially used for checking the answer sheets of
examinations having multiple choice questions.
44. Unit-3
Output Devices
The output device displays the result of the processing of raw
data that is entered in the computer through an input device.
There are a number of output devices that display output in
different ways such as text, images, hard copies, and audio or
video.
Some of the popular output devices are:
Monitor
• CRT Monitor
• LCD Monitor
• LED Monitor
• Plasma Monitor
46. Unit-3
1) Monitor
The monitor is the display unit or screen of the computer. It is
the main output device that displays the processed data or
information as text, images, audio or video.
49. Unit-3
2) Printer
A printer produces hard copies of the processed data. It
enables the user, to print images, text or any other
information onto the paper.
Based on the printing mechanism, the printers are of two
types: Impact Printers and Non-impact Printers.
51. Unit-3
Daisy Wheel Printer
A daisywheel printer is an impact printer that uses a
wheel as a print head. As the wheel rotates, a
hammer strikes the backside of the spoke and
presses it against the paper to print a character.
Advantages of a daisywheel printer
Can print letter quality characters.
Disadvantages of a daisywheel printer
Printing speed is very slow.
Cannot print graphics
52. Dot Matrix Printer
A dot-matrix printer is an impact printer that produces printed images with a
print head striking mechanism.
Most dot-matrix printers use continuous-form paper. A higher number of pins
on the print head means more dots are printed, which results in higher print
quality (i.e., a 24-pin printer has better print quality than a 9-pin printer)
The speed of a dot-matrix printer is normally measured by the number of
characters per second (cps
Unit-3
53. Unit-3
A line printer is a high-speed impact printer that prints an
entire line at a time.
The speed of a line printer is measured by the number of lines
per minute (lpm) it can print.
Line printers are often used with mainframes, minicomputers,
or with a network in applications such as manufacturing,
distribution, or shipping
54. Non Impact Printers
Laser Printer
Laser stands for light
amplification by stimulated
emission of radiation. The laser
printer is a non-impact printer. Its
working is similar to photocopying
machine. It uses laser beams to
burn special powder on page to
create a permanent image. The
power is contained in toner. Laser
printer prints complete page at a
time. It is also known as page
printer.
55. Unit-3
Inkjet Printer
An ink-jet printer is a type of non-impact printer. It prints
characters and graphics by spraying tiny drops of liquid ink on
paper. These printers can produce quality text and graphics in
both black-and-white and color including photos. A typical
inkjet printer provides resolution of 300 dots per inch. The
latest inkjet printers provide higher resolution.
56. Unit-3
A plotter is a computer printing device for printing vector
graphics
Plotter is a device that draws pictures on paper based on
commands from a computer. Plotters differ from
printers in that they draw lines using a pen. As a result,
they can produce continuous lines, whereas printers can only
simulate lines by printing a closely spaced series of dots
57. Unit-3
3) Projector
A projector is an output device that enables the user to project the
output onto a large surface such as a big screen or wall.
It can be connected to a computer and similar devices to project
their output onto a screen.
It uses light and lenses to produce magnified texts, images, and
videos. So, it is an ideal output device to give presentations or to
teach a large number of people.
58. Unit-3
A digital projector can be of two types:
Liquid Crystal Display (LCD) digital projector
Digital Light Processing (DLP) digital projector
60. Unit-3
A Central Processing Unit is also called a processor, central processor, or microprocessor. It
carries out all the important functions of a computer. It receives instructions from both the
hardware and active software and produces output accordingly.
It stores all important programs like operating systems and application software. CPU is
installed or inserted into a CPU socket located on the motherboard, it is provided with a heat
sink to absorb and dissipate heat to keep the CPU cool and functioning smoothly.
Generally, a CPU has three components:
ALU (Arithmetic Logic Unit)
Control Unit
Memory or Storage Unit
61. Unit-3
Control Unit: It is the circuitry in the control unit, which makes
use of electrical signals to instruct the computer system for
executing already stored instructions. It takes instructions from
memory and then decodes and executes these instructions.
ALU: It is the arithmetic logic unit, which performs arithmetic and
logical functions. Arithmetic functions include addition,
subtraction, multiplication division, and comparisons. Logical
functions mainly include selecting, comparing, and merging the
data. A CPU may contain more than one ALU
Memory or Storage Unit/ Registers: It is called Random access
memory (RAM). It temporarily stores data, programs, and
intermediate and final results of processing. So, it acts as a
temporary storage area that holds the data temporarily, which is
used to run the computer.
Types of CPU: Single core CPU, Dual core CPU and Quad core
CPU
62. Unit-3
Motherboard:
The motherboard is generally a thin circuit board that holds together almost all parts of a computer except
input and output devices. All crucial hardware like CPU, memory, hard drive, and ports for input and output
devices are located on the motherboard. It is the biggest circuit board in a computer chassis.
It allocates power to all hardware located on it and enables them to communicate with each other
There can be different types of motherboards based on the type and size of the computers.
CPU Slot:. It is a link between a microprocessor and a motherboard. It facilitates the use of CPU and
prevents the damage when it is installed or removed
Expansion Slot: It is also called the bus slot or expansion port. It is a connection or port on the
motherboard, which provides an installation point to connect a hardware expansion card, for example, you
can purchase a video expansion card and install it into the expansion slot
63. Unit-3
Capacitor: It is made of two conductive plates, and a thin
insulator sandwiched between them. These parts are wrapped in a
plastic container.
Inductor (Coil): It is an electromagnetic coil made of a conducting
wire wrapped around an iron core. It acts as an inductor or
electromagnet to store magnetic energy.
Other important components are:
Northbridge
PCI Slot (Peripheral Component Interconnect slot)
AGP Slot (Accelerated Graphics Port)
Heat Sink:
Power Connector
64. Unit-3
Storage Devices
A storage device is a piece of computer hardware used for
saving, carrying and pulling out data. It can keep and retain
information short-term or long-term. It can be a device inside
or outside a computer or server. Other terms for storage
device is storage medium or storage media.
A storage device is one of the basic elements of any computer
device. It almost saves all data and applications in a
computer except for hardware firmware. It comes in different
shapes and sizes depending on the needs and functionalities.
65. Unit-3-Types of Storage Devices
Magnetic Storage Device – one of the most popular types of storage used.
• Floppy diskette – A normal 3 ½ inch disk can store 1.44 MB of data.
• Hard drive – An internal hard drive is the main storage device in a computer. An external
hard drive is also known as removable hard drive. It is used to store portable data and backups.
• Magnetic strip – Magnetic tape drive stores video and audio using magnetic tape, like tape
and video tape recorders.
• Super disk – A disk drive and diskette that can hold 120 MB and 240 MB of data.
• Cassette tape – A magnetic storage device used for audio recording and playback.
• Zip diskette – Like a floppy diskette but more advanced.
Optical Storage Device – uses lasers and lights as its mode of saving and retrieving
data.
• Blu-ray disc – A digital optical storage device which was intended to replace the DVD format.
• CD-ROM disc – An optical storage device that is read-only or cannot be modified nor deleted.
• CD-R and CD-RW disc – CD-R is a recordable disc that can be written to once, while CD-RW
is a rewritable disc that can be written to multiple times.
• DVD-R, DVD+R, DVD-RW and DVD+RW disc – DVD-R and DVD+R are recordable discs
that can be written to once, while DVD-RW and DVD+RW are rewritable discs that can be
written to multiple times. The difference between the + and – is in the formatting and
compatibility.
67. Unit-3-Types of Storage Devices
Flash Memory Device – is now replacing magnetic storage device as it is economical, more
functional and dependable.
• Memory card – An electronic flash memory device used to store digital information and commonly used in
mobile electronic devices.
• Memory stick – A memory card that is removable.
• SSD – Solid State Drive – A flash memory device that uses integrated circuit assemblies to save data
steadily.
• USB flash drive, jump drive or thumb drive – A small, portable storage device connected through the
USB port.
Online and Cloud – is now becoming widespread as people access data from different devices.
• Cloud storage – Data is managed remotely and made available over a network. Basic features are free to
use but upgraded version is paid monthly as a per consumption rate.
• Network media – Audio, Video, Images or Text that are used on a computer network. A community of
people create and use the content shared over the internet.
Paper Storage – method used by early computers for saving information.
• OMR – stands for Optical Mark Recognition – A process of capturing marked data of human from forms like
surveys and tests. It is used to read questionnaires with multiple choices that are shaded.
• Punch card – A piece of hard paper used to contain digital information coming from the perforated
holes. The presence or absence of holes in predetermined positions define the data.
68. Unit-3
Software, which is abbreviated as SW or S/W, is a set of programs that
enables the hardware to perform a specific task. All the programs that
run the computer are software.
The software can be of three types: system software, application
software, and programming software.
1) System Software
The system software is the main software that runs the computer. When
you turn on the computer, it activates the hardware and controls and
coordinates their functioning. An operating system is an example of
system software.
Operating System: Microsoft Windows, Linux, and Apple Mac OS
Some other examples of system software include:
BIOS, Boot Program, An assembler, A device driver
70. Unit-3
2) Application software is a set of programs designed to
perform a specific task. It does not control the working of a
computer as it is designed for end-users
Word Processing Software
Spreadsheet Software
Multimedia Software
Enterprise Software
71. Unit-3
3) Programming Software:
It is a set or collection of tools that help developers in writing
other software or programs. It assists them in creating,
debugging, and maintaining software or programs or
applications
Some examples of programming software include: Eclipse,
Coda, Notepad, Sublime text.
72. Unit-3
Computer Network
A computer network is a group of computers linked to each
other that enables the computer to communicate with another
computer and share their resources, data, and applications.
A computer network can be categorized by their size. A
computer network is mainly of four types:
74. Unit-3
Local Area Network is a group of computers connected to each
other in a small area such as building, office.
75. Unit-3
Personal Area Network is a network arranged within an
individual person, typically within a range of 10 meters
76. Unit-3
Wireless Personal Area Network: Wireless Personal Area Network is developed by simply using
wireless technologies such as WiFi, Bluetooth. It is a low range network.
Wired Personal Area Network: Wired Personal Area Network is created by using the USB.
77. Unit-3
MAN (Metropolitan Area Network)
A metropolitan area network is a network that covers a larger
geographic area by interconnecting a different LAN to form a
larger network.
Government agencies use MAN to connect to the citizens and
private industries
78. Unit-3
WAN (Wide Area Network)
A Wide Area Network is a network that extends over a large
geographical area such as states or countries.
A Wide Area Network is quite bigger network than the LAN.
A Wide Area Network is not limited to a single location, but it
spans over a large geographical area through a telephone line,
fibre optic cable or satellite links.
The internet is one of the biggest WAN in the world.
80. Unit-3
Examples of Wide Area Network:
Mobile Broadband: A 4G network is widely used across a
region or country.
Last mile: A telecom company is used to provide the internet
services to the customers in hundreds of cities by connecting
their home with fiber.
Private network: A bank provides a private network that
connects the 44 offices. This network is made by using the
telephone leased line provided by the telecom company.
81. Unit-3
Advantages of Wide Area Network:
Following are the advantages of the Wide Area Network:
Geographical area: A Wide Area Network provides a large geographical area.
Suppose if the branch of our office is in a different city then we can connect with them
through WAN. The internet provides a leased line through which we can connect with
another branch.
Centralized data: In case of WAN network, data is centralized. Therefore, we do not
need to buy the emails, files or back up servers.
Get updated files: Software companies work on the live server. Therefore, the
programmers get the updated files within seconds.
Exchange messages: In a WAN network, messages are transmitted fast. The web
application like Facebook, WhatsApp, Skype allows you to communicate with friends.
Sharing of software and resources: In WAN network, we can share the software
and other resources like a hard drive, RAM.
Global business: We can do the business over the internet globally.
82. Unit-3
Disadvantages of Wide Area Network:
The following are the disadvantages of the Wide Area Network:
Security issue: A WAN network has more security issues as
compared to LAN and MAN network as all the technologies are
combined together that creates the security problem.
Needs Firewall & antivirus software: The data is transferred
on the internet which can be changed or hacked by the hackers, so
the firewall needs to be used. Some people can inject the virus in
our system so antivirus is needed to protect from such a virus.
High Setup cost: An installation cost of the WAN network is high
as it involves the purchasing of routers, switches.
Troubleshooting problems: It covers a large area so fixing the
problem is difficult
83. Unit-3
Topology defines the structure of the network of how all the
components are interconnected to each other. There are two
types of topology: physical and logical topology.
Physical topology is the geometric representation of all the
nodes in a network
84. Unit-3
BUS Topology
Bus topology is a network type in which every computer and
network device is connected to single cable. When it has
exactly two endpoints, then it is called Linear Bus topology.
85. Unit-3
Features of Bus Topology
It transmits data only in one direction.
Every device is connected to a single cable
Advantages of Bus Topology
It is cost effective.
Cable required is least compared to other network topology.
Used in small networks.
It is easy to understand.
86. Unit-3
RING Topology
It is called ring topology because it forms a ring as each
computer is connected to another computer, with the last one
connected to the first. Exactly two neighbours for each device
87. Unit-3
STAR Topology
In this type of topology all the computers are connected to a
single hub through a cable. This hub is the central node and
all others nodes are connected to the central node
88. Unit-3
Features of Star Topology
Every node has its own dedicated connection to the hub.
Hub acts as a repeater for data flow.
Can be used with twisted pair, Optical Fibre or coaxial cable.
Advantages of Star Topology
Fast performance with few nodes and low network traffic.
Hub can be upgraded easily.
Easy to troubleshoot.
Easy to setup and modify.
89. Unit-3
TREE Topology
It has a root node and all other nodes are connected to it
forming a hierarchy. It is also called hierarchical topology. It
should at least have three levels to the hierarchy
90. Unit-3
Features of Tree Topology
Ideal if workstations are located in groups.
Used in Wide Area Network.
Advantages of Tree Topology
Extension of bus and star topologies.
Expansion of nodes is possible and easy.
Easily managed and maintained.
Error detection is easily done.
Disadvantages of Tree Topology
Heavily cabled.
Costly.
If more nodes are added maintenance is difficult.
Central hub fails, network fails.
91. Unit-3
Mesh Topology
In this type of topology, a host is connected to one or multiple
hosts. This topology has hosts in point-to-point connection with
every other host or may also have hosts which are in point-to-point
connection to few hosts only.
There are two techniques to transmit data over the Mesh topology,
they are :
Routing
Flooding
Mesh technology comes into two types: i) Full Mesh ii) Partial
Mesh
94. Unit-3
Features of Hybrid Topology
It is a combination of two or topologies
Inherits the advantages and disadvantages of the topologies included
Advantages of Hybrid Topology
Reliable as Error detecting and trouble shooting is easy.
Effective.
Scalable as size can be increased easily.
Flexible.
Disadvantages of Hybrid Topology
Complex in design.
Costly.
95. Unit-3
World Wide Web:
The World Wide Web was invented by a British scientist,
Tim Berners-Lee in 1989. He was working at CERN at that
time. Originally, it was developed by him to fulfill the need of
automated information sharing between scientists across the
world, so that they could easily share the data and results of
their experiments and studies with each other.
In 1991, Tim created the world's first website and Web Server.
Its address was info.cern.ch, and it was running at CERN on
the NeXT computer
96. Unit-3
Definition: World Wide Web
World Wide Web, which is also known as a Web, is a collection of
websites or web pages stored in web servers and connected to local
computers through the internet.
Components of World Wide Web
These websites contain text pages, digital images, audios,
videos, etc. Users can access the content of these sites from any
part of the world over the internet using their devices such as
computers, laptops, cell phones, etc.
The WWW, along with internet, enables the retrieval and display
of text and media to your device.
97. Unit-3-WWW Operation or Working or Function
of WWW
WWW works on client- server approach. Following steps explains how the web works:
User enters the URL (say, http://www.tutorialspoint.com) of the web page in the address bar
of web browser.
Then browser requests the Domain Name Server for the IP address corresponding to
www.tutorialspoint.com.
After receiving IP address, browser sends the request for web page to the web server using HTTP
protocol which specifies the way the browser and web server communicates.
Then web server receives request using HTTP protocol and checks its search for the requested
web page. If found it returns it back to the web browser and close the HTTP connection.
Now the web browser receives the web page, It interprets it and display the contents of web page
in web browser’s window.
98. Unit-3
E-Mail
Definition: E-mail
Email is a service which allows us to send the message in electronic
mode over the internet. It offers an efficient, inexpensive and real
time mean of distributing information among people.
Characteristic of E-mail
E-Mail Address
Each user of email is assigned a unique name for his email account.
This name is known as E-mail address. Different users can send and
receive messages according to the e-mail address.
E-mail is generally of the form username@domainname. For example,
webmaster@tutorialspoint.com is an e-mail address where webmaster
is username and tutorialspoint.com is domain name.
100. Unit-3
E-mail Message Components
A.E-mail Header
The first five lines of an E-mail message is called E-mail header. The header part comprises of following fields:
1.From 2.Date 3.To 4. Subject 5.CC 6.BCC 7.From
The From field indicates the sender’s address i.e. who sent the e-mail.
Date
The Date field indicates the date when the e-mail was sent.
To
The To field indicates the recipient’s address i.e. to whom the e-mail is sent.
Subject
The Subject field indicates the purpose of e-mail. It should be precise and to the point.
CC
CC stands for Carbon copy. It includes those recipient addresses whom we want to keep informed but not exactly the
intended recipient.
BCC
BCC stands for Black Carbon Copy. It is used when we do not want one or more of the recipients to know that someone else
was copied on the message.
101. Unit-3
B.Greeting
Greeting is the opening of the actual message. Eg. Hi Sir or Hi
Guys etc.
C.Text
It represents the actual content of the message.
D.Signature
This is the final part of an e-mail message. It includes Name of
Sender, Address, and Contact Number.
102. Unit-3
Definition | Meaning of blog:
A blog (a shortened version of “weblog”) is an online journal
or informational website displaying information in reverse
chronological order, with the latest posts appearing first, at
the top. It is a platform where a writer or a group of writers
share their views on an individual subject.
There are more than 570 million blogs on the web. The
number of bloggers in the USA alone is set to reach 31.7
million users by 2020.
103. Unit-3
Purpose of Blog
Blogging to help you get to potential consumers and grab their
attention.
To rank your website higher in Google SERPs, a.k.a. increase
your visibility.
The main purpose of a blog is to connect you to the relevant
audience. Another one is to boost your traffic and send quality
leads to your website.
Great blogging makes your business look more credible, which
is especially important if your brand is still young and fairly
unknown. It ensures presence online and niche authority at
the same time.
105. Unit-3
(Continu of Blog)
Header with the menu or navigation bar.
Main content area with highlighted or latest blog posts.
Sidebar with social profiles, favorite content, or call-to-action.
Footer with relevant links like a disclaimer, privacy policy,
contact page, etc