Microprocessor is the main component of these computers as this helps in overall operation of the computer. These computers contains different modern component such as input devices, output devices, storage media, memory, etc. Microcomputer is also known as Personal Computer (PC). These computers are widely used globally due its easy to use features and affordability. There are three types of PCs. they are:
Apple/ MAC computers:
These computers were developed by Apple /Macintosh Company. They use Motorola processor and have its own technology and architecture. These computers are different from the regular PCs.
IBM computers were developed by IBM (International Business Machine) company. These computers are the most expensive computers of all. This computer uses the Intel processor.
IBM compatible computers:
These computers are made from the technology used in IBM PCs. This computer is also known as branded PC. Its underlined working principle is similar to the IBM PC. Like, IBM PCs it also uses Intel processors.
The application areas are as follows:
It is used widely over the world for the home purposes and offices for the data storage and many more.
Many of the educational institution use these computers for the various educational purposes.
Many musicians all over the world use these computers for the recording and music production.
These computers were developed in early 60's and later in 70's it was commercially used by many small companies and organization for various purposes. This computer has many clients which must be connected to it for the processing of the data as the stand-alone computers doesn't have processing capabilities. Those client computers are also known as dumb terminals. The main minicomputer is also called server as the information is fully stored in it.
The first minicomputer was developed by Digital Equipment Corporation which was named PDP-1. This computer has less processing capabilities and it is mainly loaded with simple and essential programs or application that could do simple tasks such as text processing. Although this computer uses client and server architecture network, due to the hardware and software limitation it cannot support larger network. This computer can support up to 50 terminals. It is larger than the PCs. Some of the examples of the mini computers are Prime 9755, Vax36, etc.
The application areas are as follows:
This computer was widely used in business accounting and small organization.
Scientist and engineers also used these computers for the various purposes.
These computers are also used in the academicals purposes.
It is also used for the general purposes as well.
Mainframe computers are the larger and the faster computer. This computer is similar to the minicomputer due to the presence of client server network where data are shared and received between them. Those client computers have no processing capabilities and it is considered as dumb terminal. This computer size is very huge, which is precisely 1000 sq feet. It has a central administration and processor. As it can process large amount of data it is very useful in the government areas.
Some of the examples of mainframe computers are IBM 1401, ICL 2950/10, etc. These computers are the largest computers on the basis of the size. This computer has higher storing capacity and also considered expansive as well. IBM mainframes are the most popular computers. It captured about 90% of the total market when it was released.
Following are the application areas of the mainframe computers:
This computer can be used for general purposes for the storage of the data for the future reference.
It is used by the large organization and government for the large scale data processing.
These computers are the most powerful computers of all with higher processing abilities. This computer can perform various complex tasks (calculation) very quickly. These computers are very expensive as well. It has the ability to process the data in a microsecond of a time. It can complete or solve such a complex mathematical equation in very less.
Supercomputers were first introduced by Seymour Cray at control data corporation (CDC) in 1960's. Supercomputers are mainly specialized in performing parallel task with such a high accuracy. The examples of supercomputers are CRAY-1, Deep Blue, CM5, CYBER 205, etc. It is generally used for the scientific research where many calculations are required. It produces large amount of heat. It basically uses Linux operating system. Some the supercomputer such as hydra, Deep blue is used for playing games such as Chess.
Following are the application areas of supercomputers:
Supercomputers are used by the scientist to resolve a complicated calculation for the nuclear energy research.
It is used for the weather forecasting, climate research.
It is also used by the engineers to perform various tasks.
This computer is the compact version of the PC. This computer is portable and can be used any where. It can have more processing power than the desktop PCs. It is a mobile computer as it uses rechargeable batteries to boot and run where ever we want to. The working and processing capabilities are very smooth. As it is getting cheaper and cheaper day by day, many people can afford this computer. These computers are also known as Desktop replacement computer as this computer is slowly replacing the bulky microcomputer.
There are many brands that manufacture these computers. Some of them are Lenovo, Dell, Apple, Acer, etc. IBM 5100 was the first portable PC that was used commercially. There are many types of laptop which include gaming laptop, multimedia laptop, etc. Special laptops were also designed for the network, this laptop include Net Book. Every component in the laptop is compressed and it makes handy for the many people to carry it wherever they go.
Some of the application areas are as follows:
It is used in educational and multimedia field.
In the developing countries, where there is energy crisis, people can perform various tasks whenever they want and make a most out of it.
Researcher can store data when he reaches the rural areas, where there is no electricity.
Q3. A) Explain, what is an optical scanner.
ANS Optical scanner is an input device. This device is used to digitalize the paper document i.e. it is used to convert paper document into digital format. An optical scanner is similar to photocopy machine, the only difference is that it creates the digital version of the data rather than the paper document.
When the document is scanned, the results are stored in bitmap format which is nothing but the columns and rows of dots. Each dot consists of one or more bits of data. Here if the number of bits is more, the more will be the colors and the shades of grayscale which can be presented.
b) Explain how the optical scanner works.
ANS The optical scanner follows various steps before the paper document is digitized and displayed on the screen. Following are the steps to show how optical scanner works:
The paper document is placed on the glass slab faced down.
The bright ray of light scans the paper document and takes the picture of it.
Image of the paper document is then reflected to the mirror.
The conversion of the light into analog signal is done by a chip called Charged Coupled Device (CCD).
The analog signal is converted to the digital signal by Analog to Digital Converter (ADC).
The software such as Illustrator or any other desktop publishing software receives those digital signals.
Finally, the scanned image is displayed in the screen.
a) State and explain five most common functions found in any operating system.
ANS The five most common functions of Operating System are as follows:
Os helps in the management of the memory. When more programs are executed it requires more memory usages, with this in mind, OS allocates the required memory space for the program. To reduce the usage of all the storage area available in the memory, OS creates a virtual memory for the better performance for the users interface. It allocates the memory for the system files and for the programs executed by the user.
OS distributes the resources such as printers, scanner, etc to various programs. It helps in creating balance in the system when two or more programs tries to access the resources when it is already in use. This creates a proper system where each program access resources at a time. In networking the OS manages the resources in the similar way as in the single user interface. Without it the OS would be slower and have poor performance.
I/O (Input/Output) control:
Various I/O devices such as keyboard, mouse, etc are controlled by OS. OS creates a environment such that, whenever any signal is produced from a output devices immediate response is given to the I/O devices dropping the other program which are less important. It can make the user more effectively entry the data for the various purposes and can view the required information in the moment he wants.
In OS, file can be stored and used for the future references. OS helps in storing data in memory and any other storing devices, those files can be edited or modified from the various programs or applications. OS keeps the stored data in an organized manner so that access to those data can be easier. It can also make the data more private if the user wants so that other people are not able to view the content of the data.
OS provides security to data while the data is loaded into the memory. The programs are restricted with boundaries and limitation of tasks so that they cannot get to the other program's task and make a mesh in the operating environment. In case of networking OS provides a security to prevent the access of the data for the unauthorized computer and maintain the data privacy which ultimately help in creating a safe environment for computing.
b) Name any five examples of operating system.
ANS The five examples of operating system are as follows:
Disk Operating System (DOS)