Generations of Computer

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The development of computer systems is normally discussed as the development over different generations.

With the succession of different generations, came the advancement in computer technology.

Computer Generations

Let us now discuss the development in Computer Technology over the different generations.

First Generation

• The period 1940 to 1956, roughly considered as the First Generation of Computer.

• The first generation computers were developed by using vacuum tube or thermionic valve machine.

• The input of this system was based on punched cards and paper tape; however, the output was displayed on printouts.

• The first generation computers worked on binary-coded concept (i.e., language of 0-1). Examples: ENIAC, EDVAC, etc.

Second Generation

• The period 1956 to 1963 is roughly considered as the period of Second Generation of Computers.

• The second generation computers were developed by using transistor technology.

• In comparison to the first generation, the size of second generation was smaller.

• In comparison to computers of the first generation, the computing time taken by the computers of the second generation was lesser.

Third Generation

• The period 1963 to 1971 is roughly considered as the period of Third Generation of computers.

• The third generation computers were developed by using the Integrated Circuit (IC) technology.

• In comparison to the computers of the second generation, the size of the computers of the third generation was smaller.

• In comparison to the computers of the second generation, the computing time taken by the computers of the third generation was lesser.

• The third generation computer consumed less power and also generated less heat.

• The maintenance cost of the computers in the third generation was also low.

• The computer system of the computers of the third generation was easier for commercial use.

Fourth Generation

• The period 1972 to 2010 is roughly considered as the fourth generation of computers.

• The fourth generation computers were developed by using microprocessor technology.

• By coming to fourth generation, computer became very small in size, it became portable.

• The machine of fourth generation started generating very low amount of heat.

• It is much faster and accuracy became more reliable.

• The production cost reduced to very low in comparison to the previous generation.

• It became available for the common people as well.

Fifth Generation

• The period 2010 to till date and beyond, roughly considered as the period of fifth generation of computers.

• By the time, the computer generation was being categorized on the basis of hardware only, but the fifth generation technology also included software.

• The computers of the fifth generation had high capability and large memory capacity.

• Working with computers of this generation was fast and multiple tasks could be performed simultaneously.

• Some of the popular advanced technologies of the fifth generation include Artificial intelligence, Quantum computation, Nanotechnology, Parallel processing, etc.

Applications

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A number of tasks in today’s world is computer based - filling an application, transferring fund, or doing online business everything can be done through computer application.

Easily accessible and user friendly, computer applications process the required transactions very quickly and accurately.

Computer applications are designed in such a simple manner that no qualification or training is required to use it; any person who can read and write can use computer application.

Uses of Computer Applications

In this section, we will discuss the different computer applications and their uses.

• On-line Application
• Real Time Application
• Business Application

Online Applications

Today, most of the applications are being accepted online, whether it is for opening a bank account, filling admission form, filling job application, etc.

Following are the important forms of online applications −

Banking

Most of the banks are interlinked through computer networking and offer core banking facilities. Computer networking helps maintain accounts online, offers net banking facility, makes available online transactions facility, and offers digital signature facility, the biggest advantage being that ATM machines can dispense money anytime, etc.

Ticket Booking

Ticket booking has become easier with computer networking. Flight ticket, railway ticket, and even bus ticket can be booked online with simple and easy steps.

Passport Application

If you want to apply for a new passport, you can do it by yourself online. Besides, you can also apply for other essential documents online such as PAN card, Aadhaar Card, etc.

Job Application

Today, most of the applications (private as well as government) are being filled online. Many of the organizations also conduct competitive exams leading to employment online.

Admission Application

Most of the schools and universities have made their admission applications available online; they also accept fees online.

Real-time Application

Real-time application is a computer based application program that functions in a given period of time. Or in other words, in a given period of time, a user has to perform certain functions before the time lapses.

For example, if you are making online transactions, then you have to provide the required information in a given time framework or else you will miss the chance.

Following are significant examples of real-time application −

Videoconferencing

With this technology, people can connect with each other visually from different places.

VoIP (voice over Internet Protocol)

This technology helps to make telephone calls over digital computer networks.

E-commerce transactions

This technology helps in buying and selling products over the digital computer network.

Online banking

Online banking is virtual banking from any place with the help of computer networks.

Instant messaging

This is where messages can be exchanged over the Internet instantly.

Online gaming

This enables playing of games partially or completely over the Internet.

Business Application

Different businesses have different computer applications; however, a few applications such as for maintaining the data base (of respective business), keeping employees’ records, offering online business facilities, online promotions, etc. are the common features of almost every business organization.

As such, introduction of computer technology has made business easier, simpler, and accessible 24×7.

Computer Networking Terminology

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In this chapter, we will discuss the major terminologies used in computer networking −

WAN

It stands for Wide Area Network and covers a wide area such as a city.

LAN

It stands for Local Area Network and covers a small area such as a small office or home. It physically connects all the computers located in the premises.

Internet

It is a computer network system that connects the computers of the world. It is normally connecting through WAN and LAN.

Intranet

It is a close room computer network system, as it covers a small area and only authorized people can access it.

Extranet

It is also a sort of Internet the access to which is granted only to a few.

World Wide Web (WWW)

It is the service that is used on Internet to view and search contents (in the form of web-pages).

Instant messaging (IM)

It is an online facility that facilitates us to chat or talk. Such service is provided by Skype, Google Talk, Windows Live Messenger, Yahoo Messenger, etc.

Voice over Internet Protocol (VoIP)

It is a Protocol, which is used especially for voice transfer over IP network. Likewise, it facilitates users to make phone-calls by using internet.

Really Simple Syndication (RSS)

It is a technique, which is used for the dissemination of information, articles, etc. Users normally subscribe to the RSS channel in order to receive news. After subscription, users do not need to visit the respective website rather they receive emails regarding the same.

Web log

It is a sort of online inventory (normally on a specialized topics) that consists of a series of entries. These entries are arranged in opposite chronological order. The person who maintains the weblog regularly update it with a new information.

Podcast

It is a digital file that normally contains audio or video record and is available on the Internet as well.

Social networking websites

It refers to the websites that facilitate users with a common platform where they can share their message (in text, audio, or even video form), images, videos, etc. For example, Facebook, Google+, Twitter, LinkedIn, MySpace, etc.

Chat Rooms

It is a dedicated area on the Internet that facilitates users to communicate.

Public Switched Telephone Network (PSTN)

It is a technical expression for public telephone system.

Integrated Services Digital Network (ISDN)

It is a set of communication standards that transmits voice, video, data, and other network services simultaneously.

Asymmetric Digital Subscriber Line (ADSL)

It is a sort of digital subscriber line (DSL) technology that facilitates faster data transmission.

Download

It is a process that saves data from Internet onto a personal computer.

Upload

It is a process that transfers the saved data from a personal computer to Internet server.

Dial-up

It is a technique in which a phone line is used in order to connect to the Internet.

Broadband

It is a wide bandwidth data transmission that transports multiple signals and traffic types swiftly.

Types of Computer

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All the computers that are developed are not alike rather they have different designs and features. Some computers have very high capacity as well as working speed; however, some are slow. Depending upon the requirements, computers are being developed.

Types of Computer

Depending upon the internal structure and subsequent features and applicability, computer system is categorized as follows −

Mainframe Computer

It is high capacity and costly computer. It is largely used by big organizations where many people can use it simultaneously.

Super Computer

This category of computer is the fastest and also very expensive. A typical supercomputer can solve up to ten trillion individual calculations per second.

Workstation Computer

The computer of this category is a high-end and expensive one. It is exclusively made for complex work purpose.

Personal Computer (PC)

It is a low capacity computer developed for single users.

Apple Macintosh (Mac)

It is a sort of personal computer manufactured by Apple company.

Laptop computer (notebook)

It is a handy computer that can be easily carried anywhere.

Tablet and Smartphone

Modern technology has advanced further. It has helped develop computers that are pocket-friendly. Tablets and smartphones are the best examples of such computer.

Internet

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Internet is a system that interconnects the different computer systems across the world. It uses the Internet protocol suite to link devices located in different corners of the world.

The Internet system carries an extensive range of information resources and services including World Wide Web (WWW), telephony, electronic mail, etc. It uses standard internet protocols, such as TCP/IP and HTTP, etc.

An internal web comprises of all Hypertext Transfer Protocol (HTTP) nodes on a private network; for example, an organization’s LAN or WAN.

Features of Internet

Let us now discuss the features of Internet. The features are described below −

Accessibility

An Internet is a global service and accessible to all. Today, people located in a remote part of an island or interior of Africa can also use Internet.

Easy to Use

The software, which is used to access the Internet (web browser), is designed very simple; therefore, it can be easily learned and used. It is easy to develop.

Interaction with Other Media

Internet service has a high degree of interaction with other media. For example, News and other magazine, publishing houses have extended their business with the help of Internet services.

Low Cost

The development and maintenance cost of Internet service are comparatively low.

Extension of Existing IT Technology

This facilitates the sharing of IT technology by multiple users in organizations and even facilitates other trading partners to use.

Flexibility of Communication

Communication through Internet is flexible enough. It facilitates communication through text, voice, and video too. These services can be availed at both organizational and individual levels.

Security

Last but not the least, Internet facility has to a certain extent helped the security system both at the individual and national level with components such as CCTV camera, etc.

Internet Software

Internet Software comprises of all the tools needed for networking through computer. Following are a few important components of the Internet Software −

• Transmission Control Protocol/ Internet Protocol (TCP/IP)
• Dialer Software
• Interment Browser

Internet Applications

Internet applications are server-based applications. Following are a few Internet Applications −

• World Wide Web (WWW)
• Electronic mail (e-mail)
• File Transfer Protocol (FTP)
• Telnet (i.e., log-in to the computer located remotely)
• Internet Relay Chat (IRC) (Real time video chatting)

Operating System

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An operating system is the fundamental basis of all other application programs. Operating system is an intermediary between the users and the hardware.

Operating system controls and coordinates the use of hardware among application programs. The major services of an operating system are −

• Memory management
• Disk access
• Creating user interface
• Managing the different programs operating parallel
• Likewise, it controls and manage the hardware’s working

Applications of Operating System

Following are the major applications of an operating system −

• An operating system is accountable for the formation and deletion of files and directories.

• An operating system manages the process of deletion, suspension, resumption, and synchronization.

• An operating system manages memory space by allocation and de-allocation.

• An operating system stores, organizes, and names and protects the existing files.

• Further, an operating system manages all the components and devices of the computers system including modems, printers, plotters, etc.

• In case, if any device fails, the operating system detects and notify.

• An operating system protects from destruction as well as from unauthorized use.

• An operating system facilitates the interface to user and hardware.

Types of Operating System

Following are the major types of operating system −

• Disk Operating System (DOS)
• Windows Operating System
• Unix Operating System

Let us now discuss each operating system in detail.

Disk Operating System

MS-DOS is one of the oldest and widely used operating system. DOS is a set of computer programs, the major functions of which are file management, allocation of system resources, providing essential features to control hardware devices.

DOS commands can be typed in either upper case or lower case.

Features of DOS

Following are the significant features of DOS −

• It is a single user system.
• It controls program.
• It is machine independence.
• It manages (computer) files.
• It manages input and output system.
• It manages (computer) memory.
• It provides command processing facilities.
• It operates with Assembler.

Types of DOS Commands

Following are the major types of DOS Command −

• Internal Commands − Commands such as DEL, COPY, TYPE, etc. are the internal commands that remain stored in computer memory.

• External Commands − Commands like FORMAT, DISKCOPY, etc. are the external commands and remain stored on the disk.

Windows Operating System

The operating system window is the extension of the disk operating system.

It is the most popular and simplest operating system; it can be used by any person who can read and understand basic English, as it does not require any special training.

However, the Windows Operating System requires DOS to run the various application programs initially. Because of this reason, DOS should be installed into the memory and then window can be executed.

Elements of Windows OS

Following are the significant element of Windows Operating System (WOS) −

• Graphical User Interface
• Icons (pictures, documents, application, program icons, etc.)
• Taskbar
• Start button
• Windows explorer
• Mouse button
• Hardware compatibility
• Software compatibility
• Help, etc.

Versions of Windows Operating System

Following are the different versions of Windows Operating System −

Version	Year	Version	Year
Window 1.01	1985	Windows XP Professional x64	2005
Windows NT 3.1	1993	Windows Vista	2007
Windows 95	1995	Windows 7	2009
Windows 98	1998	Windows 8	2012
Windows 2000	2000	Windows 10	2015
Windows ME	2000	Windows Server 2016	2016
Windows XP	2001

Unix Operating System

The Unix Operating System is the earliest operating system developed in 1970s. Let us consider the following points relating to the Unix Operating System −

• It is an operating system that has multitasking features.

• It has multiuser computer operating systems.

• It runs practically on every sort of hardware and provides stimulus to the open source movement.

• It has comparative complex functionality and hence an untrained user cannot use it; only the one who has taken training can use this system.

• Another drawback of this system is, it does not give notice or warn about the consequences of a user’s action (whether user’s action is right or wrong).

Analog and Digital

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The following table highlights the basic differences between analog and digital −

Analog	Digital
Its functions on physical analog system.	It functions on discrete numbers system.
The calculations in this system are primarily converted to equations and later converted into electrical signals.	The calculations in this system are converted into binary numbers (i.e., 1s and 0s).
To function, it requires physical analog.	To function, it requires discrete numbers.
It gives output in the form of ‘graph’.	It gives output in the form of discrete values.
Accuracy comparatively is less.	Accuracy is very high.
Performs at a low speed.	It performs at a very high speed.
Difficult to make changes, as it is less flexible.	It is highly flexible.
It has memory of low capacity.	It has memory of high capacity.
Its application is limited to certain applications.	Its application is applicable to a number of applications.
It is hardly applicable for the business applications.	It is very much suitable for the business applications.
It cannot process alpha-numeric data.	It can process alpha-numeric data.
It requires RF technology.	It requires IP networking.
Static channel assignment.	Automatic channels exist as required.