UNIT II

INTRODUCTION TO DATA PROCESSING

Data processing: is "the collection and manipulation of items of data to produce meaningful

information.

1. Numerical Data

2. Character Data

3. Logical Data

Data Processing Cycle

1. Origination

2. Input

3. Processing

4. Output

5. Distribution

6. Storag

STEPS IN DATA PROCESSING

1. Identifying the Data.

2. Input of Data.

3. Manipulation of Data.

4. Output of Information.

5. Storage of Information

KINDS OF DATA PROCESSING

1. Manual Processing

2. Electronic Data processing.

OBJECTIVES OF DATA PROCESSING

1. Handle huge volume of data

2. Qualitative and quantitative information

3. Proper and Timely Information

4. Storage and Retrieval of data

5. Helps in decision Making

6. Improves in Productivity

7. Maintaining performance at optimum level

8. Efficient office management.

DATA BASE

A database is an organized collection of data. The data are typically organized to model

relevant aspects of reality in a way that supports processes requiring this information

CHARACTERISTICS OF DATABASE

Centralized and integrated data file which consists of all the data used by a company.

1. Organized and structured in a different manner than the conventional

sequential file organization.

2. Organization is such that duplication of data is minimized if not

eliminated entirely

3. Permits access to any of all data quantities by all applications with equal

case.

4. Emphasis the independence of programs as well as data and application

programs and including it as part of the database.

5. Stored on a direct access storage device.

6. Provides for the definition of logical relationships, which exist between

various records in the database

DATA BASE MANAGEMENT SYSTEM

A database management system is a set of software programs that allows users to create, edit and update

data in database files, and store and retrieve data from those database files. Data in a database can be

added, deleted, changed, sorted or searched all using a DBMS.

OBJECTIVES OF DATA BASE

1. Controlled Redundancy

2. Data Independence

3. More Information at low cost

4. Accuracy

5. Recovery from Failure

6. Easy for learning and use

7. More Information to management

8. Reduce the access style

9. Integrity

OBJECTIVES OF DATA BASE

1. Provide for mass storage of relevant data.

2. Make access to the data for the year.

3. Provide prompt response to user request for data.

4. Make the latest modifications to the database available immediately.

5. Eliminate redundant data.

6. Allow multiple users to be active at one time

7. Allow for growth in the data base system.

8. Protect the data from physical harm

9. Unauthorized access

COMPONENTS OF DATA BASE

At least one person who owns and is responsible for the data base.

A set of rules and relationships that defines and governs the interactions

among elements of the data base.

People who put data into the data base

People who get data out of the data base.

The data base itself

ADVANTAGE OF DATA BASE MANAGEMENT

1. Eliminates data redundancy.

2. Ability to associate related Data.

3. Program data independence.

4. Improvement of the interface between the user and the system

5. Increased security and integration of data.

UNIT III

COMPUTER COMMUNICATION

Data Communication: Is the transmission of electronic data over some

media. Data communication is the active process of transporting data from one

point to another. Networks are communication system designed to convey

information from a point of origin to a point of destination. Note that they are

communication system, not computer system. The operative word is

communication, the transfer of information from one device to another.

Basic Elements of a Communication System

1. Sender – This creates the message to be transmitted.

2. Medium – That carries the message.

3. Receiver - This receives the message.

Computer Network

Computer Networking is the process of inter connecting two or more

computers so that the user can communicate with each other, share

resources and overcome other limitations of standalone system.

Advantages of Networking

1. Hardware resource sharing.

2. Sharing of Database.

3. Sharing of software.

4. Communication between users.

5. Decentralized data processing.

6. Security of data.

Types of networking

1. Wide area network – (WAN): WAN is made up of number of

autonomous computers distributed over a wide geographical area.

Features of WAN

It operates by means of the international telephone network.

Unlike LAN which owned by their users.

Data transmission is somewhere slower.

The WAN compose any of the following system configurations

Single nodes

Clusters

LAN‟s

Advantage of WAN

The WAN allows access to database at remote site, enabling

exchange of data.

If a remote node fails, remaining nodes on the network can still

exchange data.

If the network fails, the local mode can still access its own

database

The data used on daily basis by the sales offices resides at the local

site making it easier to retrieve quickly.

The local offices can maintain the data more effectively.

As a site‟s database grows large in its system‟s storage capacity

can be easily upgrade without affecting the transfer of data

between other nodes on network

Metropolitan Area Network

Metropolitan area network covers a wider area than a local area network.

It operates at high speeds over distances sufficient for a metropolitan

area.

Local Area Network

A LAN is a system of interconnected microcomputers, sharing common

resources like disks, printers etc.

Local Components

Workstation

File server

Gateway

Network Interface Unit

Active Hub

Passive Hub

LAN Cable

Network Operating System

Applications software

Protocol.

UNIT IV

INTERNET AND E – COMMERCE

Internet: An Internet can be defined as a network connecting an

affiliated set of clients using standard internet protocols.

FEATURES OF INTERNET

Simplicity of use: The software that is used access the internet is

comparatively easy to learn and simple to use.

Breadth of access: The internet is a global network like the

telephone network. Its access is not conditioned by geographic

boundaries.

Synergy with other media: A part from using the existing

telecommunication technology. It supports or complements other

media.

Internet applications or services of Internet

World Wide Web: It is one of the popular services available on

the internet which has subset of text, images, animation, video,

sounds and other multimedia in a single interface.

Electronic Mail: The electronic mail or Email is a fast and easy

and inexpensive way to communicate with other internet user

around the world.

File Transfer Protocol (FTP): It is a system of rules and a

software program that enables a user to log on to another computer

and transfer information between it and his /her computer. Or in

simple it is internet utility software used to upload and download

files.

Telnet: The word “TELNET” is derived from telecommunication

and network and is a protocol that allows a user to log on to a

remote computer. Telnet is also known as remote login, which

means connecting one machine to another in such a way that a

person may interact with another machine.

Internet Relay Chat (IRC): IRC is a service on the internet that

allows people to communicate in real time and carry on

conversation via the computer with one or more people.

Chatting and Instant Messaging: Chat programs allow user on

the internet to communicate with each other by typing in real time

wherein they can log into chat rooms to exchange comments and

information about the topics addressed on the site.

Internet Telephony: Internet telephone is the use of the internet

rather than the traditional telephone company infrastructure, to

exchange spoken or other telephonic information. It consists of

hardware and software that enable people to use the internet as a

transmission medium for telephone calls.

Video Conferencing: Video conferencing uses the same

technology as IRC but also provides sound and video pictures. It

enables direct face to face communication across network.

Newsgroups (Usenet): Newsgroups are international discussion

groups that focus on a particular topic and helps in gathering

information about that topic.

Mailing Lists (List Server): The internet is home to a large

community of individuals who carry out active discussions

organized around topic oriented forums that are distributed via e-

mail. This method of internet communication is known as mailing

list it enables people with similar interests from all over the world

to communicate and share information with each other.

MOBILE COMPUTING : Mobile computing is a generic term

describing your ability to use technology „un tethered‟ (wireless) that is

not physically connected or in remote or mobile environments. The term

is evolved in modern usage such as that it requires that the mobile

computing activity be connected wirelessly to and through the internet

or to and through a private network.

ELECTRONIC COMMERCE: It is a process of searching, choosing,

buying and selling of products or services on the electronic network, it

uses the computer and communication networks for promoting products,

selling, and delivery collection and delivery service.

IMPORTANCE OF E- COMMERCE

Low setup cost: Anybody can set up a website. To market a

product large retail showrooms are not required just a website

showing the characteristics of the product including cost details