COMPUTER FUNDAMENTALS
1. What is a computer?
A computer is a tool or instrument that helps in computation. Computation includes addition, subtraction, multiplication, division, comparison of numbers, manipulation of texts, logical decisions etc. We use calculators in our routine for carrying out calculations. However, the scope of application of a calculator is thus very limited. A computer, in contrast, can store a series of instructions and huge information and data in its memory and process a complete job.
Efficiency of the computer depends on the set of instructions given to it. It exactly does what it has been told to do. Precise, clear and correct instructions should be given to the computer to enable it to carry out the operations correctly. When the instructions are faulty and not clear, the results produced by the computer will also be faulty and not clear. This phenomenon of wrong output of data due to wrong input of instructions/data is termed as Garbage in Garbage out (GIGO).
2. What are the advantages of computer?
• Very high speed processing
• Large capacity for storage and retrieval of data
• Perfect accuracy
• Automatic working capability
• Diligence
• Versatility
3. What are the limitations of computer?
• Can not think on its own
• Can not learn by experience
• Can not take independent decisions on its own.
• Requires human intervention for each any every step
4. Explain the evolution of computers.
Increasing need for numerical calculations, storage of data and information etc. with minimum of mental and manual efforts led to invention of computers.
• ABACUS, used for calculations, was the earliest devise that qualifies as a computer widely used 6000 years ago. The ABACUS was built using the idea of place values.
• John Napier developed Logarithm, a tabular system of numbers through which many arithmetical calculations were simplified, in 1617.
• Napier also invented a set of rods which were carved from bones and used for multiplication. These were called Napier Bones.
• Slide Rule, based on the principle of logarithm, a calculating device was invented by William in 1620.
• Blaise Pascal, a Frenchman, invented a mechanical unit in 1642 that could add and subtract, using a set of toothed wheels. This ‘calculator’ was the first digital machine.
• Pascal’s machine was further improved by a German mathematician Gottfried that could add, subtract, multiply, divide and extract roots.
• In 1822, Charles Babbage built the ‘Difference Engine’. This could do only one kind of calculations.
• In 1833, Charles Babbage designed and worked on Analytical Engine. It was a general purpose computer designed to solve almost any type of problem. It contained most of the elements we find in modern digital computer systems. Hence, Charles Babbage is considered as Father of modern computer.
• Joseph Jacquard invented punch cards in 1801. Punch card had holes punched in it. These were used by him to produce weaving pattern on the cloths.
• In 1880, Dr.Herman Hollerith used punched cards for data processing by building a tabulating machine that could punch holes in cards and read them as well. This machine worked on electricity and had mechanical parts and could handle 50 to 75 cards per minute. The system was very slow and card jams and data destruction were common problems. Punching machine, Verifying machine, Interpreter, Sorter, Collators, Tabulator were some of the machines used in this system.
• In 1944, Howard Alken built MARK1, the first digital computer, at Harvard University. It lacked speed but had the ability to continuously perform complex arithmetic functions without frequent human intervention. It was partly electronic and partly mechanical machine.
• In 1936, Alan Turing from Cambridge University submitted his brilliant logical analysis on ‘artificial intelligence’. His contribution on the development of electronic computers remains the single biggest contribution ever made to the science.
• In 1930, Germans developed a mechanical machine called as ‘ENIGMA’ for coding military messages.
• In 1939, Britain initiated to build machines that could decipher Enigma’s codes. The world’s first giant computer using values was built called the ‘Colossus’.
• In 1942, USA started to develop an electronic computer. In 1946, it could put to operation ‘ENIAC’ (Electronic Numerical Integrator and Calculator), made in University of Pennsylvania. John Mauchly and J.Presper Eckert were the two people involved in its development. This computer was made of 18,000 vacuum tubes. ENIAC could process the data at great speeds (though not comparable to today’s computers).
• UNIVAC-1 was the first business oriented computer developed in 1952 used by US Bureau of Census.
5. Explain the ‘Generations of computers’.
A generation is a rough period of time over which there are no major changes or development in that particular field. Every change in technology has been treated as a new ‘generation’ of computers. Each generation has its own advantages and disadvantages.
