Tuesday, April 5, 2011

History of computer in Nepal

Computer is a programmable machine that stores and retrieves data and performs high speed logical and mathematical operations.
        The first computer brought in Nepal was IBM 1401 which was brought by the government in lease for the population census of 1972 (2028 BS). Later in 1975 (2031 BS)YantrikSarinikaran Kendra (Electronic Data Processing Centre) was established which was later called as National Computer Centre (NCC). Again for the population census of 2038 BS ICL 2950/10 computer having 64 terminals was brought in Nepal by the aid of UNDP. After 2039 B.S. Microcomputer like; Apple, Vector, Sirius were introduced in the capital. From that time computers have been used in different government sectors like banking, agriculture, universities etc. Now there are thousands of computers institutes providing computer educations, assembling, maintenance etc. throughout the kingdom of Nepal. Now a day in every sector there the people use computer to do the work easier.

Disadvantages of Computer

        We see that computers have great impact on our societies. They are even changing the way we work. They make the way of work very easier, effective and reliable. Use of computer is to reduce the working time in any field. Along with the advantage there are certain disadvantages also. There may be cases if misuse in the banks, leakage or personal information, etc.
        When a person is using computer for marketing, office work, collections of information’s, etc. his activities is recorded. One can misuse this record. So individual privacy is not guaranteed. Someone can play misbehave on computer. He can erase certain important data. He may take away some important and private data. Extensive use of computers for the job, which is labour oriented, will cause unemployment. But in industries computers can be used for machine control and process control etc. for which earlier electronic or electromechanical control system were employed. Such applications of computer do not much affect labour employment.
       

Classification of the computer on the basis of brand

Computers can be classified into various classes according to on the basis of working principle, on the basis of size, on the basis of brand. On the basis of brand computers are classified in to three types IBM PC, IBM compatible, Apple/Macintosh.
                The computers manufactured by IBM (International Business Machine) company are called IBM computers. The microcomputers of IBM companies are called IBM PC. IBM is one of the leading companies in computer industry. Computers developed on the principle of IBM computers are called IBM Compatible. It can perform all the tasks that an IBM computer does. They are less expensive than original (IBM) computers. In others words, a personal computers manufactured by the Apple Companies are called Apple Computers. They are specially used in Desktop-Designing. They are quite expensive than IBM and IBM Compatible. The operating system and other peripherals are completely different then IBM and IBM Compatibles.

Generation of computer

Depending on the device used, system architecture, processing mode and language used in the computers are categorised in the five generation. The development of different types of memories devices has given a sequence of development of computers from mainframe to microcomputers.
              We can consider the duration of First-generation starts from 1946. The computers using the vacuum tubes as a memories unit are known as first-generation computers. The second generation computers used transistors as a memories unit. Processing speed ofthis generation is faster than first generation computer. The third generation computers used Integrated circuit chips in place of the transistors. The sized of the computers was generally reduced, the speed of processing was high, they were more accurate and reliable. The computers design using VLSI, as a memory unit is known as Fourth generations computers They have very high speed of processing; they are 100% accurate, reliable,diligent, and versatile. The fifth-generation computers are under development stage. They will have artificial intelligence and will be able to understand natural language.

Classification of computer on the basis of working principal

      Computers are classified in to various classes according to On the basis of working principle, On the basis of size, and on the basis of brand.On the basis of working principle computer are classified in to three types Ana log computer, Digital computer, and hybrid computer. Ana log computer measures continuous type of data and uses a physical quantity like electric current, voltage, temperature, etc. to present and process the data. It represent numbers by a physical quantity; that is, they assign numeric values by physically measuring some actual property, such as the length of an object, an angle created by two lines, or the amount of voltage passing through a point in an electric circuit. The computer which accepts discrete data as per the electric signals is known as digital computer. Basically , digital computers counts digits, which represent numbers or letters. The computers based on binary digits i.e. 0 and 1 are called digitals computer. It represents each and every information in terms of single numbers and processes the information by using standard arithmetic operations. Hybrid computer is the combination of the feature of Ana log and Digital computers.

Classification of computer on the basis of size

 On the basis of size computer are classified in to four types Mainframe computer, Minicomputer, Microcomputer and Super computer.
                 Mainframe computers are large computers which processes at high speed and occupied a large space. This has a large capacity to handle huge number of records. More than 100 people can work at a time and communicate with different countries with wide area networks via satellite. Minicomputers are medium in size then mainframe computers but large then microcomputers. They are less powerful then super and mainframe but powerful then microcomputers. They are specially used in data processing, programming, desktop publishing field. A small computer driven by a single integrated circuit and designed for use by one person is called microcomputer. They are widely used at home and offices. Mani brands, model and sized are available in microcomputers. Micro computers can be sub categorized in todesktop computer, Laptop computer, Palmtop computer. A computer that is capable of working at great speed, and can thus process a very large amount of data with an accepted time.


Sunday, April 3, 2011

History of Computer

                      The history of computer starts from 4000 years ago. History of computer means the gradual change in the concepts over a long period of time. Around fifth century Hindu philosophers developed a new method of counting the numbers from 0 to 9 can be preformed with the help of fingers. The development of counting device called ABACUS and it is developed by Chinese people. It was first used for computation's in 3000 BC.
                        In 1614AD, a Scottish mathematicians John Napier discovered the concept of logarithms. In 1617AD, he constructed a set of rods called Napier Bones for doing mathematical calculation easily. After the invention of logarithms in 1617AD,William Oughtered invented the slide rule in 1620. This device was made on the principal of logarithms. Pascals calculating was developed by Blaise Pascal in 1642. It was a mechanical calculator that used toothed wheels and gears. Leibniz's calculator was made by a German philosopher G.V Leibniz's in 1671AD it was based on pascal principal. In 1822AD an English Mathematicians invented a machine called Difference engine. with mechanical memory to store results . A