Define Computer? Explain what are different types of Computer.

Semester :-1

Unit:-1

Define Computer? Explain what are different types of Computer.
Ans:-
          Computer is an electronic device, which stores data, process it and gives the results consistently, accurately at very high speed according to our instructions. The word computer is derived from the word "Compute". It means perform or calculate. That's way, the computer is also called as calculating device. The computers can broadly classified into three types namely
 a) Analog Computers
b) Digital Computers
c) Hybrid Computers
a) Analog Computers:-
                                            The analog computer operate by measuring instead of counting. The analog computer works on the supply on continuous electrical signals. The display is also continuous and its output is in the form of graphs.
                In Analog Computer, the input data is a continuously changing electrical or non-electrical information. Computations are carried out with physical quantities such as Voltage, length, Current, Temperature etc. The device measuring such quantities are called analog devices. The advantages of analog computer is that all calculation take place in parallel and hence it is very fast. It is used for engineering and scientific application. But their accuracy is poor as compared to digital computer.
Characteristics :-  

1. It operates by measuring.
2. It requires by measuring.
3. It function on continuously quantity.
4. The output is usually represented in the form of graph.
5. The accuracy of the output is poor.
6. It has limited memory space.
7. It is not versatile i. e. It has limited applications.
8. Speed is very low.
9. These computers are not suitable for business and industry.
10. The calculations are first converted into equations and later converted into electrical signals.

b) Digital Computers :-

                                             As the name implies, the digital computer with quantities represented as digits. In digital computer, both numeric and non-numeric information are represented as string of digits.

             In Digital Computer, the input data is discrete in nature. It is represented by binary notation in the form of "0"s and" 1"s digital computers are much faster than analog computers and are more accurate. Digital computers are largely used for business and scientific applications.

              The basic operation performed by a digital computer is addition. Hence, the other operation such as multiplication, division, subtraction and exponentiation are first changed into "Addition and then compute".

Characteristics :-

1. It operates by Counting
2. It functions on discrete numbers
3. The calculations are converted into binary numbers
4. The output is represented in the form of discrete values
5. Its accuracy is good
6. It has large memory space
7. It is versatile in nature
8. It is suitable for a number of applications
9. It processing speed is high
10. It is highly suitable for business applications

c) Hybrid Computers :-

                                             The Hybrid Computers combines the features of both the analog and digital computers. These are used for special Analytical applications. weather-monitoring system and device used in Intensive Care units (ICU) of the hospitals are example of hybrid Computers.

                 Further more, computers are classified depending on the application as: special purpose Computers and General purpose Computers.

       As the name implies the special purpose computers are designed to perform a specific task or a special application.