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8. Storage
The computer has an in built memory where it can store a large amount of data. You can also store data in secondary storage devices such s floppies, which can be kept outside your computer and can be carried to other computers.
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Many packages are designed in such away that they can be used for a variety of similar problems. For example, payroll packages are sometimes produced in forms that enable them to be set up and used by different companies each having slightly different ways in which they need to produce their payroll. The most abundant selection of packages is available on personal computers, with the more popular packages selling in tens of thousands of copies or even hundreds of thousands of copies.
ii. System software. These are programs, with associated documentation, that control the way the computer operates or provide facilities that extend the general capabilities of the system. Within the set of systems software for a given computer there is usually a program, or suite of programs, called the operating system. The operating system controls the performance of the computer by doing a variety of jobs to ensure the proper, orderly and efficient use of hardware by applications programs. Most applications programs can only work when used in conjunction with the operating system. Other systems software may extend the capabilities of the operating system further, for example, by providing programs that
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can monitor how efficiently the hardware is being utilised by the software.
Hardware
Hardware is the name given to all the physical devices found in a computer system. Whether looking at a small computer on a desktop or at a large computer in the computer room, where the devices look like large, inert metal cabinets, there is little visible evidence of the phenomenal speeds at which data is being processed within. It is the programs which put life into the hardware.
Key Functions of a Personal Computer
Before looking at specific PC components, it is worth taking a few moments to consider the motions that are performed by a computer:
Input- Entry of raw data; for example, typing names and addresses on a keyboard or transmitting a picture from a digital camera
Processing- Manipulation of the raw data to produce useful information. Purpose of a computer for example, sorting or indexing the names and address adding effects to the picture.
Output - Transformation of the data into information, perhaps in a non-computerized format; for example, printing mailing labels from a database or displaying the picture in a brochure
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Storage:- Retention of the data until it is needed: for example, filing names and addresses in a database or archiving the picture in an online library. With a basic understanding of these key functions, the role of each of the components of a PC becomes much clearer.
THE COMPUTER HARDWARE SYSTEM
Source: Management Information System
The diagram above is a simple illustration of the computer hardware system. It can also be regarded as the diagrammatic representation of the flow of data/information between t HIS parts that make up the computer system.
ALU
CONTROL UNIT
MAIN MEMORY
INPUT UNIT OUTPUT UNIT
AUXILIARY STORAGE
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FUNCTIONAL UNITS
In order to carry out the operations mentioned in the previous section the computer allocates the task between its various functional units. The computer system is divided into three separate units for its operation.
They are 1) arithmetic logical unit. 2) control unit, and 3) central processing unit.
Arithmetic Logical Unit (ALU)
After you enter data through the input device it is stored in the primary storage unit. Arithmetic Logical Unit performs the actual processing of the data and instruction. The major operations performed by the ALU are addition, subtraction, multiplication, division, logic and comparism. Data is transferred to ALU from storage unit when required.
After processing the output is returned back to storage unit for further processing or getting stored. Control Unit (CU)
The next component of computer is the Control Unit, which acts like the supervisor seeing that things are done in proper fashion. The control unit determines the sequence in which computer programs and instructions are executed. Things like processing of programs stored in the main memory, interpretation of the instructions and issuing of signals for other units of the computer to execute them. It also acts as a switchboard
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operator when several users access the computer simultaneously.
Thereby it coordinates the activities of computer's peripheral equipment as they perform the input and output. Therefore it is the manage of all operations mentioned in the previous section.
Central Processing Unit (CPU)
The ALU and the CU of a computer system are jointly known as the central processing unit may call CPU as the brain of any computer system. It is just like brain that takes all major decisions, makes all sorts of calculations and directs different parts of the computer functions by activating and controlling the operations.
Personal Computer Configuration
Now let us identify the physical components that make the computer work. These are
1. Central Processing Unit (CPU)
2. Computer Memory (RAM and ROM) 3. Data bus
4. Ports
5. Motherboard 6. Hard disk
7. Output Devices and
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8. Input Devices
All these components are inter-connected for the personal computer to work.