Information Technology

Information Technology

BASICS OF COMPUTER Introduction Historical Perspective Classification Of Computers Elements Of Computing Process Characteristics of Computer Advantages and Limitations of Computers

Introduction  Computer is an electronic device which can compute and process data.  Computer can store, process and retrieve data whenever required.  Computers can do computations with not only all kinds of numbers but also with alphabets, pictures, sound, images and voice (multimedia)  It is capable of producing accurate results from the inputs given and is very reliable.

Historical Perspective Generatio Years n

Circuitry

Characterized By

First

1951 to 1959

Vacuum tubes

Magnetic drum and Magnetic tape

Second

1959 to 1963

Transistor Magnetic cores and s magnetic disk

Third

1963 to 1975

Integrated Mini computers Circuit accessible by multiple users

Fourth

1975 to present

VLSI

PC and user friendly micro programmers

Classification Of Computers  Supercomputers  Mainframes  Minicomputers  Workstations and Microcomputers  Computers on the move – portable computers (laptop, notebook, etc)  Docking station  Palmtop computers  Smart cards  Embedded computers

Classification of Computers Cont’d According to Technology  Analog  Digital  Hybrid According to Size and Capacity  Micro Computer  Mini Computer  Mainframe Computer  Super Computer

Elements Of Computing Process  Hardware – the physical parts of the computer  Software – the programmers that tell the computer what to do.  Data  People  Procedures All the above are necessary for the computer to perform a useful task.

Characteristics of Computer They are fast. They are reliable They are accurate They can store massive amounts of information They can move information very quickly from one place to another

Advantages and Limitations of Computers Advantages Speed – computations can happen very fast

Limitations Incapability to take decisions on their own, like human beings

Versatility in terms of Capability to distinguish taking inputs – it can valid from invalid data process multiple types of data Accuracy – results generated by a computer are very accurate

Requires regular maintenance

Parts of a Computer  Input Devices   

Keyboard Mouse Scanner

 Output Devices  

VDU Printers

Input Devices

Keyboard The keyboard is very much like a standard typewriter with few additional keys. When any key is pressed it sends electronic signal with unique identification to the computer. There are 101 keys in standard keyboard but nowadays keyboards with more than 101 keys are also available.

Input Devices Mouse It is an input device that controls the movement of the cursor on a display screen. A mouse is a small object that can be rolled along a hard flat surface. The name is derived from its shape, which looks a bit like a mouse. As the mouse is moved, the pointer on the display screen moves in the same direction. Mouse contains at least one button and sometimes as many as three, which have different functions depending on what program is running.

Input Devices Scanner It is one of the device, mostly used in designing etc and provides input to computers. These inputs are used for processing and manipulation, there are some specific scanners built for special purposes like OCR, MICR or BCR.

Output Devices Visual Display Unit (VDU) It is a device looks like TV – this is used to display output, termed as monitor. It uses cathode ray tube (CRT) to display text, images, drawings etc when a key is pressed Control Unit (CU) gets intimated and sends instructions for drawing that character on the monitor, this is example of VDU functionality.

Output Devices Printers : A printer is a device that prints text or illustrations on paper and in many cases on transparencies and other media. There are many different kinds of printers: a. Daisy-wheel printer b. Dot-matrix printer c. Ink-jet printer d. Laser printer e. WD and LED printers f. Line printer g. Thermal printer

Parts of a Computer Cont’d.. Characteristics of Printers:  Quality of type  Speed  Impact or Non impact  Graphics  Fonts Other parts :  Plotter  Sound cards and Speakers  3D audio

Computer Networks A network is a group of two or more computer systems linked together. A network consists of five basic components: 1. 2. 3. 4. 5.

Terminals Telecommunication Processors Telecommunications Channels and Media Computer Telecommunication Software

Computer Networks A network is a group of two or more computer systems linked together. A network consists of five basic components: 1. Terminals – include video display terminals and other end user workstations. Any input/output device that uses a network to transmit or receive data is a terminal. 2. Telecommunication Processors These are devices which support data transmission and reception between terminals and computers. These devices such as modems, multiplexers and front-end processors perform a variety of control and support functions in a network.

Computer Networks Cont’d 3. Telecommunications Channels and Media : The media over which data are transmitted and received are called telecommunication channels. They use combinations of media such as copper wires, coaxial cables, fiber option cables, microwave systems to interconnect the other components of a network. 4. Computer : Networks interconnect computers of all sizes and types so that they can carry out their information processing assignments. 5. Telecommunication Software : These are programmers that reside in host computer systems, communication control computers and end user computers.

Types of Computer Networks From end user’s point of view, there are two basic types : Local Area Networks (LAN) : This spans a relatively small area and are confined to a single building or group of buildings. Number of LANs connected by telephone lines or radio waves is called WAN. Wide Area Networks (WAN) : This spans a relatively large geographical area and typically a WAN consists of two or more local area networks.

Types of Networks Cont’d Internet : Internet is made up of millions of computers linked together around the world in such a way that information can be sent from any computer to any other 24 hours a day. It is a loose amalgam of thousands of computer networks. Intranets: Networks used within an organization is an intranet or an internal web. Extranets: This network connects the organization's intranet through the internet gateway and would be able to use the intranet.

Computer viruses A computer virus is an actively infectious computer program that place copies of itself into other applications and programs but not into data files. A virus is a manmade program or piece of code that causes an unexpected, usually negative, event.

Anti Virus Programs (AVP) Cleaning a disk from file viruses involves deleting the virus code from the infected file. While cleaning a disk of boot sector / partition table viruses, involves deleting the virus code from the respective sectors and copying the boot programs back to their original space. Examples Of Famous AVP’s : Norton, Mcfee.

Operating Systems Operating Systems are devised to optimize the manmachine capabilities. Programs are held permanently in the computer memory freeing thereby the operator from inputting a program for each application. An operating system can be defined as an integrated system of program which supervises the operations of the CPU, controls the input/output system of programs which supervises and translates the programming languages into machine languages and provides various support services. The operating systems are base on the concept of modularity.

Operating Systems All the working details are taken care by the operating system. It takes care of all the intermediate activities required in accomplishing the task submitted. E.g. Microsoft Windows, DOS, XENIX, Mac OS, OS/2, UNIX, MIVS, etc

Functions of Operating Systems There are six basic functions that an operating system can perform : 1. 2. 3. 4. 5. 6.

Schedule Jobs Manage Hardware and Software Resources Maintain System Security Enable Multiple User Resources Sharing Handle Interrupts Maintain Usage Records For large systems, the operating system has even greater responsibilities and powers. It is like a traffic policeman ; it makes sure that different programs and users running at the same time do not interfere with each other.

Classification of Operating Systems Operating Systems can be classified as : • Multi-user/Time sharing • Multi-processing • Multi-tasking • Multi-threading • Foreground/background processing • Real-time

Introduction to MS Word MS Word is word processing software where text could be manipulated to produce documents such as memos, class notes, letters, term papers and other written text. Not only could computers process numbers – they could also process words. Nowadays word processing has become one of the principal applications used on personal computers.

Introduction to MS-Excel Excel is known as a spreadsheet application. A spreadsheet still uses the idea of a large sheet of paper into which numbers are entered. A spreadsheet is a highly interactive computer program that consists of a collection of rows and columns that are displayed on screen in a scrollable window. A workbook is an excel file where the data is stored and it consists of many worksheets. Worksheet is a grid made up of horizontal rows and vertical columns. Macros is a very small program that allows you to customize Excel so that it makes tasks easier.

Introduction to MS-Power Point

Power Point helps to easily create presentations for many purposes, including lectures, research reports, meeting handouts and agendas, speaker introductions and flyers. Presentations can be used to display diverse information in a clear and concise manner. It helps to: • Create presentations with the AutoContent Wizard • Add and delete slide from presentations • Customize a slide layout • Add Notes • User the Web to view presentations

Accounting Packages Accounting, in simplest terms is keeping track of our Income, Expenses, Assets and Liabilities. This is true for a business, for a household and for an individual. Some basic documents used in financial accounting system are: 1. Voucher 2. Journal 3. Ledger Some main reports prepared in the financial accounting system are : 1. Trial Balance 2. Profit and Loss Report 3. Balance Sheet

TALLY

EES

Tally is a versatile accounting package and is also based on a windowing interface. All screens in Tally are viewed as windows processing the following : - A title bar that displays the name of the application - A tally icon to the left (of the user) that pulls down a menu comprising restore, move, size, minimize and maximize menu items - Three small buttons to the right (of the user) that activates minimize, maximize and closure of the window. - These menu items and buttons are invoked through the usual short cut keys and hot keys as any other window based application.

TALLY

EES Cont’d….

The edition of the package is Tally ees 6.3 ; ees stands for extended enterprise system version 6.3. It is licensed for unlimited users connected to a single computer or network server over a local area network. The visible advantages of the package are simplicity, flexibility, speed, scalability and real time access to data across locations and even with other applications.

TALLY

EES Cont’d…..

Other features of Tally: Backup Provisions : Tally provides excellent backup facilities Easy exit to Operating System : Tally allows users to migrate to the operating system by just typing Esc key. Unencrypted files Inadequate controls on automatic entries Inflexibility of document formats Inability to add/rename field

E.X. Next Generation E-X (Everything else is Complex) is a very user friendly Business Accounting Software from Tata Consultancy Services. Launch in 1991 it was one of the first packaged applications launched in India. Soon the wings of E-X spread across other countries. E-X follows a simple front-end structure and seamlessly integrates all the transactions into primary and secondary Accounting Books as also the Final Reports.

E.X. Next Generation All accounting entries in E-X have been classified into the following groups : • • • • • • • • • • •

Receipts Payments Purchase Sales Purchase Return Sales Return Journal Debit Note Credit Note Cash and Bank Transfers (Contra) Withdrawals / Deposits

E.X. Next Generation Analysis Parameters – Analysis of financial data helps to find out the details about business sensitive information. Analysis information in E-X is just like adding a slip or a tag on a voucher giving details of a specific nature like the name of the person who has made the expense or income.

Computer Aided Audit Techniques Controls and Auditing in Computer Environment - General Controls : controls create a framework of overall control over the computer based activities of the firm. These controls are categorized into four : organizational and management controls, application systems development and maintenance controls, access controls, other controls - Application Controls : are designed to provide reasonable assurance that the recording, processing and reporting of data through computer systems are properly performed for specific applications. These controls are broken into three groups – Input controls, processing controls, output controls.

Computer Aided Audit Techniques Some of the techniques available are: 1. Audit Software 2. Core Image Comparison 3. Database Analyzers 4. Embedded Code 5. Log Analyzers 6. Mapping 7. Modeling 8. On-line Testing 9. Program Code Analysis 10. Program Library Analyzers 11. Snapshots 12. Source Comparison 13. Test data 14. Tracing

Computer Aided Audit Techniques Using all these tools and techniques, it is necessary to monitor access, investigate apparent security violations and take appropriate remedial action. There are three kinds of auditing : Statement Auditing – based on SQL statement presented Privilege Auditing – based on auditing actions connected to certain privileges Object Auditing – It is possible to audit all actions taken against specific objects. Key tables aren’t changed very often could for instance be audited for changes. An auditor should evaluate a wide range of controls when conducting an audit of a database system.

Database Design MS Access is a powerful multi-user DBMS developed by Microsoft Corp. It can be used to store and manipulate large amount of information and automate repetitive task, such as maintaining an inventory, e.g. generating invoices. Database Management System (DBMS) A DBMS is a set of systems software programs that manages the database files.

Databases Database is a collection of related and ordered information, organized in such a way that information can be accessed quickly and easily.. In a database, data are integrated and related so that software programs provide access to all the data. A database system comprises of five major parts namely : 1. Hardware 2. Software 3. People 4. Procedures 5. Data

Databases A single user DBMS supports only one user at a time. A multi-user DBMS supports multiple users at the same time. A DBMS that supports a database located at a single site is called a centralized DBMS. A DBMS that supports a database distributed across several different sites is called a distributed DBMS.

Types of Database Implementation Models • • •

Hierarchical Network Database Model Relational Database Model – e.g. Oracle, Sybase, Informix, CA-INGRES

Some basic terminologies Fields Record Table

Types of Database Implementation Models Structured Query Language (SQL) – is the most widely accepted query language for almost all RDBMS. A computer language designed to organize and simplify the process of getting information out of database in a usable form, and also used to reorganize data within databases. SQL is most often used on larger databases on minicomputers, mainframes and corporate servers. The three basic data functions provided by SQL are : Data Definition Language Data Management Language Data Control Language

FOXPRO FOXPRO comes under the category of Relational Database Management Systems It offers all the features of a programming language and power tools for designing such as customized menus, screens and reports. FoxPro is very popular mainly due to its menu driven interface and interactive environment. It is available for both DOS and WINDOWS environments.

MS Access 2000 Microsoft Access 2000 for Windows is a database management system, or DBMS which helps us, manage data stored in a computer database. MS Access 2000 is a DBMS package from Microsoft. The latest version of Access 2000 provides a plethora of new features designed to help us use the Internet and develop World Wide Web applications.

E-Commerce E-Commerce is defined as buying and selling of products and services over the Internet, but there are many more aspects to it. E-commerce is a system that includes not only the transactions that center on buying and selling goods and services to directly generate revenue, but also those transactions that support revenue generation, such as generating demand by those goods and services, offering sales support and customer service or facilitating business partner.

E-Commerce From a communication perspective, electronic commerce is the delivery of information, products, services or payments via telephone lines, networks or any other means From a business process perspective, electronic commerce is the application of technology towards the automation of business transactions and workflows. From a service perspective, electronic commerce is a tool that addresses the desire of firms, consumers and management to cut service costs while improving the quality of goods and increasing the speed of service delivery. From an online perspective, electronic commerce provides the capability of buying and selling products and information on the Internet and other online services.

E-Commerce E-commerce endeavors to improve the execution of business transactions over various networks. These improvements may result in more effective performance and greater economic efficiency. E-Commerce enables the execution of information laden transactions between two or more parties using interconnected networks. E-Commerce can be viewed as a production process that converts digital inputs into value added outputs through a set of intermediaries.

Web Commerce • Electronic Data Interchange (EDI) – is a “transfer of structured data for processing from computer to computer using agreed formats and protocols. • Electronic Fund Transfer (EFT) • Value Added Networks (VAN)

Internet Internet is the world’s largest network. It is not a single network but a global interconnected network of networks providing free exchange of information. The data is transmitted in the form of digital signals. These signals are converted into a form suitable for analog transmission. The process is called modulation. The process of transforming the analog signal into digital representation at the receiving end is called demodulation. Thus the modification of frequency to carry data is called modulation. The device used for this purpose is called a modem.

Internet Cont’d Connections : These are basically two ways of getting connected to the internet 1. Dedicated Access – helps to access the internet directly and throughout the day 2. Dial up Access – the computer can be connected to the net by dial up access by means of a modem. Other ways Bulletin boards Mail call Wireless Systems

Internet Services E-Mail or Electronic Mail is an electronic form of regular mail. The Internet Service Provider (ESP) delivers the message conveyed in the email to the recipient. One of the major advantages of email is that it is very easy to use, very fast and much cheaper than sending regular mail.

World Wide Web The World Wide Web (WWW) is a part of the net is a collection of web pages. It contains information that can be a combination of text, pictures and hyperlinks. The web is a graphic medium and most of the web pages have an image. The web browser is the software with which we can use the different aspects of the Internet like Usenet newsgroup, file libraries and so on.

Hyperlink • Hyperlinks are also known as links. Each link in a web page refers to another web page. When we click on a link, the browser fetches the page connected to the link which in turn can contain more links to other places over the net. A hyperlink can be a word, a group of words, a picture of a part of a picture. It helps in retrieving information from different places and is easy in retracing paths as each page having a link contains a reference to the previous page. In this system, all the related information can be listed under the main topic. The system of interlinked documents is known as Hypertext.

Hypertext Hypertext is the method of presenting information through highlighted items. Hypertext system allows creation of links from two topics to the same document effecting connections between the pieces of information

Search Engines Search engines and directories are web searching features. A directory is meant for browsing. It is organized in a particular manner for easy and productive browsing. The bigger directories have built in search engines which are more convenient as both browsing through the directory and using the search engine are possible. The directories that come with the built-in engines are Yahoo!, Lycos and Excite. On the other side, the search engines alike Alta Vista, Open Text, Inktomi and WWW worm do not have a directory.

Internet Opportunities Cryptography : Cryptography is the science of securing data. It is the process of transforming plain text or original information into an unintelligible form so that it may be sent over unsafe channels of communication. Encryption : covers all techniques to encipher or encode a transmission of information. Replacing the letters in a message with a corresponding number or by the next letter in the alphabet is a form of encryption.

Front page 98 Introduction to Front Page 98 – In the front page editor you create, design and edit World Wide Web pages. As text, images, tables, form fields and other elements are created to the page the Front Page Editor displays them as they would appear in the Web browser. FrontPage Editor creates all the HTML code so it is not necessary to learn how to create Hypertext Markup Language (HTML).

Enterprise Resource Planning ERP covers the techniques and concepts employed for the integrated management of businesses as a whole, from the viewpoint of the effective use of management resources, to improve the efficiency of an enterprises. ERP packages are integrated software packages that support the above ERP concepts.

Utilities of MS- Office and Outlook 2000 Calendar : The Outlook 2000 calendar is an electronic scheduler used to organize your day. Scheduler : This features requires Microsoft Exchange. This procedure works only if you have been given permission to schedule this resource.

Outlook 2000 Microsoft Outlook 2000 is the Windows messaging system. It includes customizable email, scheduling, task and contact tracking tools to help you efficiently manage your office activities. Outlook 2000 also includes a group called Other Shortcuts. The most common shortcut bar (Outlook Shortcuts) are : Outlook Today, Inbox, Calendar, Contacts, Tasks, Journal, Notes, Deleted Items