Friday, July 29, 2016

computer awareness-generation -111

Computer Generations
Generation in computer terminology is a change in technology a computer is/was being used. Initially, the generation term was used to distinguish between varying hardware technologies. But nowadays, generation includes both hardware and software, which together make up an entire computer system.

There are totally five computer generations known till date. Each generation has been discussed in detail along with their time period and characteristics. Here approximate dates against each generations have been mentioned which are normally accepted.

Following are the main five generations of computers

S.N. Generation & Description
1 First Generation

The period of first generation: 1946-1959. Vacuum tube based.

2 Second Generation

The period of second generation: 1959-1965. Transistor based.

3 Third Generation

The period of third generation: 1965-1971. Integrated Circuit based.

4 Fourth Generation

The period of fourth generation: 1971-1980. VLSI microprocessor based.

5 Fifth Generation

The period of fifth generation: 1980-onwards. ULSI microprocessor based
 

computer awareness -types

Computer - Types
Computers can be broadly classified by their speed and computing power.
Sr.No. Type Specifications
1 PC (Personal Computer) It is a single user computer system having moderately powerful microprocessor
2 WorkStation It is also a single user computer system which is similar to personal computer but have more powerful microprocessor.
3 Mini Computer It is a multi-user computer system which is capable of supporting hundreds of users simultaneously.
4 Main Frame It is a multi-user computer system which is capable of supporting hundreds of users simultaneously. Software technology is different from minicomputer.
5 Supercomputer It is an extremely fast computer which can execute hundreds of millions of instructions per second.
PC (Personal Computer)
A PC can be defined as a small, relatively inexpensive computer designed for an individual user. PCs are based on the microprocessor technology that enables manufacturers to put an entire CPU on one chip. Businesses use personal computers for word processing, accounting, desktop publishing, and for running spreadsheet and database management applications. At home, the most popular use for personal computers is playing games and surfing Internet.
Although personal computers are designed as single-user systems, these systems are normally linked together to form a network. In terms of power, now-a-days High-end models of the Macintosh and PC offer the same computing power and graphics capability as low-end workstations by Sun Microsystems, Hewlett-Packard, and Dell.
Personal Computer
Workstation
Workstation is a computer used for engineering applications (CAD/CAM), desktop publishing, software development, and other such types of applications which require a moderate amount of computing power and relatively high quality graphics capabilities.
Workstations generally come with a large, high-resolution graphics screen, large amount of RAM, inbuilt network support, and a graphical user interface. Most workstations also have a mass storage device such as a disk drive, but a special type of workstation, called a diskless workstation, comes without a disk drive.
Common operating systems for workstations are UNIX and Windows NT. Like PC, Workstations are also single-user computers like PC but are typically linked together to form a local-area network, although they can also be used as stand-alone systems.
Work Stations
Minicomputer
It is a midsize multi-processing system capable of supporting up to 250 users simultaneously.
Mini Computer
Mainframe
Mainframe is very large in size and is an expensive computer capable of supporting hundreds or even thousands of users simultaneously. Mainframe executes many programs concurrently and supports many simultaneous execution of programs
Main Frame
Supercomputer
Supercomputers are one of the fastest computers currently available. Supercomputers are very expensive and are employed for specialized applications that require immense amount of mathematical calculations (number crunching). For example, weather forecasting, scientific simulations, (animated) graphics, fluid dynamic calculations, nuclear energy research, electronic design, and analysis of geological data (e.g. in petrochemical prospecting).
Super Computer

computer awareness -overview-1



Computer Overview
Today’s world is an information-rich world and it has become a necessity for everyone to know about computers. Purpose of this tutorial is to introduce you about computer and its fundamentals.
Functionalities of a computer
Any digital computer carries out five functions in gross terms:
Takes data as input.
Stores the data/instructions in its memory and use them when required.
Processes the data and converts it into useful information.
Generates the output
Controls all the above four steps.
Computer
Definition
Computer is an electronic data processing device which
accepts and stores data input,
processes the data input, and
generates the output in a required format.
Advantages
Following list demonstrates the advantages of computers in today's arena.
High Speed
Computer is a very fast device.
It is capable of performing calculation of very large amount of data.
The computer has units of speed in microsecond, nanosecond, and even the picosecond.
It can perform millions of calculations in a few seconds as compared to man who will spend many months for doing the same task.
Accuracy
In addition to being very fast, computers are very accurate.
The calculations are 100% error free.
Computers perform all jobs with 100% accuracy provided that correct input has been given.
Storage Capability
Memory is a very important characteristic of computers.
A computer has much more storage capacity than human beings.
It can store large amount of data.
It can store any type of data such as images, videos, text, audio and many others.
Diligence
Unlike human beings, a computer is free from monotony, tiredness and lack of concentration.
It can work continuously without any error and boredom.
It can do repeated work with same speed and accuracy.
Versatility
A computer is a very versatile machine.
A computer is very flexible in performing the jobs to be done.
This machine can be used to solve the problems related to various fields.
At one instance, it may be solving a complex scientific problem and the very next moment it may be playing a card game.
Reliability
A computer is a reliable machine.
Modern electronic components have long lives.
Computers are designed to make maintenance easy.
Automation
Computer is an automatic machine.
Automation means ability to perform the given task automatically.
Once a program is given to computer i.e., stored in computer memory, the program and instruction can control the program execution without human interaction.
Reduction in Paper Work
The use of computers for data processing in an organization leads to reduction in paper work and results in speeding up a process.
As data in electronic files can be retrieved as and when required, the problem of maintenance of large number of paper files gets reduced.
Reduction in Cost
Though the initial investment for installing a computer is high but it substantially reduces the cost of each of its transaction.
Disadvantages
Following list demonstrates the disadvantages of computers in today's arena
No I.Q
A computer is a machine that has no intelligence to perform any task.
Each instruction has to be given to computer.
A computer cannot take any decision on its own.
Dependency
It functions as per a user’s instruction, so it is fully dependent on human being
Environment
The operating environment of computer should be dust free and suitable.
No Feeling
Computers have no feelings or emotions.
It cannot make judgement based on feeling, taste, experience, and knowledge unlike a human being
Top 10 Tallest Mountains in the World
S.No. Highest Mountains
1 Mt. Everest (8850 m)
2 K2 (Godwin Austen) (8611 m)
3 Kanchenjunga (8598 m)
4 Lhotse (8501 m)
5 Makalu (8475 m)
6 Lhote Shar (8383 m)
7 Dhaulagiri (8167 m)
8 Manaslu (8163 m)
9 Cho Oyu (8153 m)
10 Nanga Parbat (8125 m)

World top Ten Countries by Largest Mountain Ranges
S.No. Country
1 Andes ( 7242 KM )
2 Rocky Mountains ( 6035 KM )
3 Himalayas / Karakoram / Hindu Kush ( 3862 KM )
4 Great Dividing Range ( 3621 KM )
5 Trans Antarctic ( 3541 KM )
6 Brazilian East Coast Range ( 3058 KM )
7 Sumatran / Javan Range ( 2897 Km )
8 Tien Shan ( 2253 KM )
9 Estern Ghats ( 2092 KM )
10 Altai ( 2012 Km ), Central New Guinean Range ( 2012 KM ), Urals ( 2012 KM )