Basic of computer learning

Basic of computer learning:

# Concept, Importance and Characteristics of Computer    

                                        

The full form of COMPUTER is Common Operating Machine Particularly Used for Trade, Education and Research. Technically speaking, the term computer does not have a full form. The term computer is essentially derived from the word 'compute', which means to calculate. Nevertheless, there is a hypothetical full form of computer, which is said to be Commonly Operated Machine Particularly Used for Trade, Education and Research The computer is a multi-tasking programmable electronic machine which performs the calculations and processes information with astonishing speed. It can calculate thousands of informations with flash speed and almost unfailing accuracy. The computer can perform both computation and logical action at enormous speed. The two principle characteristics of a computer are:

• It responds to a specific set of instructions in a proper manner.
• It can execute a prerecorded list of instruction (a program)

In other words, a computer is an electronic device that manipulates information, or data. It has the ability to store, retrieve, and process data. Before we talk about different types of computers, let's talk about two things all computers have in common: hardware and software. Hardware is any part of your computer that has a physical structure, such as the keyboard or mouse. It also includes all of the computer's internal parts, which you can see in the image below. Software is any set of instructions that tells the hardware what to do and how to do it. Examples of software include web browsers, games, and word processors. Below, you can see an image of Microsoft PowerPoint, which is used to create presentations.

# IMPORTANCE OF COMPUTER

The computer is important in a variety of ways. For example, a difficult and time-consuming task can be done in no time and in an easy way. The computer provides better and effective way to manage a large amount of information to every individual, organization, business, government and institution. The value of computer lies in the ability to perform quickly and accurately. The computer can help in producing better quality products, help in teaching and assist in elimination human error.

a.) Solving numerical problems

Solving numerical problems

One of the most difficult and most important jobs performed by computers is the solution of complicated problems involving numbers. computers can solve those problems amazingly and quickly. The computer can perform a simple numerical problem to complicated numerical problem.

b.) Storing and retrieving information

People use computers to store large quantities of information. information stored on a computer is sometimes called a database. The database can be enormous. For example, a country's entire census might be contained in a single database. A computer can search a huge database to find a specific piece of information. In addition, the information can be changed easily and quickly. The efficiency with which computers store and retrieve information makes them valuable in a wide range of professions.

c.) Creating and displaying document and picture

creating and displaying image

Computers can store a huge number of words in a way that make it easy to manipulate them. For this reason, word processing is one of the most important and widespread uses of a computer. Computers are also important in the publishing industries. For example, most books and magazine are typed on a computer. Graphics is the use of a computer to make pictures.

# CHARACTERISTICS OF COMPUTER

Characteristics of computer

 

Every computer has certain common characteristics irrespective of their type and size. The computer is not just adding machines; they  are capable of doing complex activities and operations. They can be programmed to do complex, tedious and monotonous tasks. Computers are what they are because of the following characteristics:

i.) Word length 

A digital computer operates on binary digits i.e 0 and 1. It can understand information only in terms of 0s and 1s. A binary digit is called  a bit. a group of 8 bits is called a byte. The number of bits that a computer can process at a time in parallel is called its word length. Commonly used word length are 8,16,32 or 64 bits. Word length is the major of the computing power of a computer. When we talk of a  32-bit computer, it means that it's word length is 32 bits.

ii.) Speed 

character of a computer

The calculation in the computer is at very high speeds. For example, a micro computer can perform millions of instructions per second  as many times without any mistake. The speed increases, as the power of computer increase. For example, a super computer can  operate at speed measures on nanoseconds and even picosecond.

iii.) Storage

storage device of a computer

         

The computer has main memory and auxiliary memory. The computer can store a large amount of data. With more and more auxiliary  storage devices, which are capable of storing huge amounts of the data, the storage capacity of a computer is virtually unlimited. The  reason that makes computer storage unique is not that it can store huge amount of data, but the fact that it can retrieve the information  that the user wants in a few seconds. For example, computer dictionaries are available and the contents of this software version are  the same as that of the printed dictionary.

iv.) Accuracy

The accuracy of a computer is very high unless the input is given correctly. In most cases, the error is because of human factor rather  that technology mistake. For example, if the person input wrong code or the data is corrupted,the processing result is also wrong or corrupted. So if wrong input is given, the output also will be wrong- GIGO (Garbage In Garbage Out)

v.) Versatility

Computers can perform activities ranging from simple calculation like arithmetic calculation, to a complex calculation like launching  a missile, which it makes a computer a versatile machine. some application area of computers like a business, bank medical  diagnosis, science and technology, communication and astronomy, so it is a versatile machine.

vi.) Diligence

Diligence means being constant and determined in effort and application. The computer can perform the repetitive task without  being a bore and it never gets tired. It can work continuously for several hour or day without getting bored and tired. Unlike human  beings, a computer is free from tiredness, weakness, lack of concentration and monotony. Computers can perform activities  ranging from simple calculation like arithmetic calculation, to a complex calculation like launching a missile, which it makes a  computer a versatile machine. 

vii.) Automation

A computer is an automatic machine, capable of functioning automatically once they are an appropriate set of instruction and data  provided to the computer. Once the task is initiated on a computer it can proceed continuously. The computer can be  programmed to perform a series of a task involving multiple programs. Computers are capable of these levels of automation if the  instruction is provided correctly. 

viii.) Reliability

Computers are used widely as they are reliable. The computer never gives the wrong result as long as the input is given correctly.  The probability of error in the computer is negligible. A Huge amount of verities of data like monetary transaction, banking account,  personal information is stored in a computer with the strong reliability to the computer. The computer has become an integral part of our lives and is helping us in improving the standard living, enhancing the quality  products, providing better healthcare, assisting in teaching and learning and other however computer have many limitations like  lack of intelligence, lack of reasoning capabilities and other.

# ADVANTAGES AND DISADVANTAGES OF COMPUTER

1.ADVANTAGES 

• The computer can perform a complex operation in a short time. 

• The computer can process a large volume of data. 

• Computer can work continuously for a long time 

• A single computer can perform multiple tasks such as watching a movie, playing games, listening song and  others. . 

• Computer increases the curricular performance of the student. 

• The computer does not make a mistake.  

2.DISADVANTAGES 

• The computer does not have a brain and cannot decide  itself.                                                                                                        

•  It does not have its own intelligence

• The computer does not have emotion and  
  feelings.  

• It needs electricity to operate.  

• It cannot operate itself, unless, a human command is given.

# Generation of Computer and Their Features

Things to remember :👇👇👇

GENERATIONS OF COMPUTERS :

Computer generations classification is mainly based on the basic devices used. Also, the considerations are the architecture,  languages, modes of operation, etc. The function performed by the computer and the speed of their operations have been changing  since the old days to the most modern computer. Based on the period of development and the features incorporated, the computers are  classified into different generations- First generation to Fifth generation. This is called the computer generation. 

Classification and Time Period of Computer are :

1. First Generation Computer (1945-1955) 

2. Second Generation Computer (1957-1963) 

3. Third Generation Computer (1964-1971) 

4. Fourth Generation Computer (1972 onward) 

5. Fifth Generation Computer (Present and future)

1.) First Generation Computer (1945-1955) 

Vacuum tube

First generation computers were characterized by the fact that operating instructions were made to order for the specific task for which  the computer was to be used. It was operated on the ' Principle of Thermionic Emission". In the first generation computer, vacuum tubes as CPU, magnetic drum for data storage , and machines languages were used for giving  instruction. The computer of this generation was very large in size called room-sized computers. The programming of first generation  computers was done in machine languages (0s and 1s). Afterward, assembly languages were developed and used in first generation  computer.

Features of first generation computers: 

• Technology used: vacuum tube 
• Machines languages were used to instruct the computer.  
• Magnetic core memory was used as primary memory. 
• Electrostatic tubes, Parer tape, punch card, magnetic tape 
• Punched card, printing devices were used for input/output operations and store the result. 
• It occupies very large space, slow processing, inefficient and unreliable due to low accuracy.  
• Power consumption was very high and it generated much heat. 
• It could only perform straight forward simple numerical calculation.  
• Computer used to be much expensive 

The example of first generation computers is ENIAC, UNIVAC,EDVAC, and EDSAC. 2.) Second

      2.Second  Generation Computer (1957-1963)

Second generation computer replaced machine language with assembly language, allowing abbreviated programming codes to replace  long, difficult binary codes. 

 The transistor was developed in this generation. A transistor transfers electric signals across a resistor. A transistor was highly reliable  compared to tubes. The transistor was far more superior in performance on account of their miniature size, smaller power consumption, and heat  production rate. The second generation computer used these semiconductor devices. 

Some of its features of second generation computer are: 

• Technology used: Transistor 
• Operating speed was in terms of a microsecond. 
• Assembly language and machines independent language such as COBOL (Common Business Oriented Language) and  FORTRAN (Formula Translation) were introduced the size of the computer. 
• Magnetic core memory was used as primary memory. 
• Magnetic drum and magnetic tape were used as secondary memory.  
• Power required to operate them was low. 
• It could perform scientific calculation such as solving differential equations.  
• Storage capacity and use of computers are increased.

3.) Third Generation Computer (1964-1971) 

Transistors were an improvement over the vacuum tube, but they still generated a great heat, which damaged the computer's sensitive  parts. The quartz eliminated this problem. Transistors were replaced with an integrated circuit known popularly as chips. Scientist managed to fit many components on a single  chip. As a result, the computer became ever smaller as more components were squeezed on the chip.

IC was first designed and fabricated by Jack S Kilby at Texas Instrument and by Robert S Noyce at Fairchild independently. IC is a  circuit consisting of a large number of electronic components placed on a single silicon chip by a photo-lithographic process. Magnetic disks began to replace magnetic tape for auxiliary and video display terminals were introduced for the output of data.  Keyboards were used for the input of data. A new operating system was introduced for automatic processing and multi-programming. These computers were highly reliable, relatively expensive and faster. High-level programming languages continued to be a developer.  The example of third generation computers is IBM-360 series, ICL-900 series, and Honeywell 200 series.

Features of the third generation computers are:

• The technology used: IC (Integrated Circuit). 
• Transistors were replaced by IC in their electronic circuitry. 
• High-level languages like FORTAN , BASIC and other are used to develop programs.  
• Semiconductor memory like RAM and ROM were used as primary memory. 
• Monitor and keyboard were introduced for data input and output respectively.  
• Multiprogramming facility was developed. 
• The computer was used in census calculation, military, banks and industries.  
• Size, cost, power requirement and heat generation decreased. 
• Processing speed and storage capacity used of computer increased.

4.) Fourth Generation Computer (1972 -onward)

The invention of microprocessor chip marked the beginning of the fourth generation computers. Semiconductor memories replaced magnetic core memories. The invention of microprocessors led to the development of microcomputer or the personal computer. The first microprocessor called Intel 4004 was developed by American Intel Corporation 1971. This computer has faster generation language and application software for microcomputers became popular and allowed home and  business users to adapt their computers for word processing, spreadsheet manipulating, file handing and graphics. In this generation, the concept of computer networks and CD-ROMs came into existence. 

Features of the fourth generation computer are:

• Technology in use: VLSI is introduced and used Microprocessor-based technology.  
• Problem-oriented fourth generation language (4GL) is used to develop the program.  
• Semiconductor like RAM, ROM and cache memory is used as a primary memory. 
• Magnetic disks like hard disk, optical disk (CD,DVD), Blue-ray disk, flashes memory (memory chip, pen drive) are used as  secondary memory. 
• E-mail, Internet and mobile communication are developed.  
• Advanced, user-friendly, web page software are developed. 
• Size, cost, power requirement, heat generation decreased compared to the previous generation.  
• Operating speed, storage capacity ,use of computer increased compared to the previous generation

The example of the fourth generation computer is IBM-PC, HP laptops, Dell laptop , Mac notebook etc.

5.) Fifth Generation Computer (Present and future)

Fifth generation computer

Fifth generation computer

The aim is to bring machines with genuine IQ, the ability to reason logically and with real knowledge of the word. Thus, this computer  will be totally different, totally novel and totally new than last four generations of computer. Fifth generation computer was based on Artificial Intelligence (AI) and that is still developing process, but not yet a reality i.e this  computer is incomplete. The scientists are working on it still. These computers will be able to converse with people and will be able to mimic human sense, manual skills, and intelligence.

Features of the fifth generation computers are:

• Technology to be used: These machines will incorporate Bio-chip and VVLSI (Very Very Large Scale Integration) or Ultra-Large  Scale Integration (ULSI) 
• The computer will have Artificial Intelligence (AI).  
• Natural language will be used to develop programs.  
• The computer will have parallel processing in full fledge. 
• The operating speed will be in terms of LIPS(Logical Inference per Second) 
• These aim is to solve highly complex problems, which require great intelligence and expertise when solved by people.  Quantum computation, molecular and nanotechnology will be used completely.