This document provides an introduction to data processing, databases, computer communication, the internet, and e-commerce. It defines key terms like data processing, the data processing cycle, types of data, database management systems, computer networks, internet applications, and electronic commerce. It also lists objectives and characteristics of databases, advantages of networking, types of computer networks, and the importance of e-commerce.
1. 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.
2.
3.
4.
5.
6.
Origination
Input
Processing
Output
Distribution
Storag
STEPS IN DATA PROCESSING
1.
2.
3.
4.
5.
Identifying the Data.
Input of Data.
Manipulation of Data.
Output of Information.
Storage of Information
2. KINDS OF DATA PROCESSING
1. Manual Processing
2. Electronic Data processing.
OBJECTIVES OF DATA PROCESSING
1.
2.
3.
4.
5.
6.
7.
8.
Handle huge volume of data
Qualitative and quantitative information
Proper and Timely Information
Storage and Retrieval of data
Helps in decision Making
Improves in Productivity
Maintaining performance at optimum level
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.
3. 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.
2.
3.
4.
5.
6.
7.
8.
9.
Provide for mass storage of relevant data.
Make access to the data for the year.
Provide prompt response to user request for data.
Make the latest modifications to the database available immediately.
Eliminate redundant data.
Allow multiple users to be active at one time
Allow for growth in the data base system.
Protect the data from physical harm
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.
2.
3.
4.
Eliminates data redundancy.
Ability to associate related Data.
Program data independence.
Improvement of the interface between the user and the system
4. 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.
2.
3.
4.
Hardware resource sharing.
Sharing of Database.
Sharing of software.
Communication between users.
5. 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.
6. 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.
7. 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
8. 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.
9. 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 email. 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