Chapter - 1 : Introduction to Computer System
Subject: Computer Fundamentals | ▒
Definition of Computer :
A computer is a programmable electronic device, which has the capacity to process or manipulate a given set of organized data at a very high speed, to generate the desired information, according to the instructions provided.
Programmable: able to be provided with coded instructions for the automatic performance of a task.
Electronic devices are components for controlling the flow of electric currents for the purpose of information processing and system control. In other words, a computer is an advanced electronic device that takes raw data as input from the user and processes it in ALU (Arithmetic Logic Unit) under the control of a set of instructions (called program), produce the result (output), and saves it for the future use.
The process is a series of actions or steps taken in order to achieve a particular end.
Data is a collection of raw facts and figures without any sequence which is processed to produce information. Facts or data can be any set of items. Data can be words, numbers, symbols, graphics, etc.
Example: name, number of days, sale figures, etc.
Information is an organized, meaningful and useful interpretation of data. Information is data that has been converted into meaningful results.
Examples are time-table, merit list, report card, printed documents, payslips, and receipts, etc.
Characteristics of a Computer System
Characteristics are the features or qualities belonging typically to a person, place or thing and serving to identify them. There are five major characteristics of a computer system
The speed of something is the rate at which it moves or travels.
The speed of the computer determines how fast you can open and run a program. The speed of the computer depends on the amount of RAM and Processor speed.
A computer is an electronic device. Data and the instructions to process the data travels inside the computer as electrons that move at an incredible speed, equivalent, to that of light. Thus, the time taken by the computer to process a set of data as per the instructions is measured not as hours, minutes and seconds, but as a thousandth of a second - milliseconds, millionth of a second - microseconds, billionth of a second - nanoseconds.
How to check the amount of RAM and processor speed?
In Mac OS,
Apple Icon >> About This Mac >> More Info
In Windows OS,
Start Menu >> Control Panel >> System
Processor speed indicates how fast your computer runs and is measured in megahertz (MHz) and gigahertz (GHz).
RAM indicates the storage space your computer uses to store and read data. The more memory the computer has, the faster it can run and open programs.
The accuracy of a computer is consistently high, which is not in the case of a human being; one could commit approximately one error per 50 - 100 calculation. A computer commits no error and has the same efficiency and reliability with any amount of data.
The accuracy of a computer depends on using bug-free computer chips as well as the quality of input.
Computers have huge storage capacity. Data can be permanently stored on other devices like disks and tapes.
Being an electronic device, a computer does not suffer from human traits like tiredness, lack of concentration and boredom.
After several millions of instructions, it will perform with the exactly the same accuracy and speed as the first one, provided the working conditions, such as power temperature and humidity conditions are maintained within the desired level.
Computers, therefore, are better than human beings in performing voluminous and repetitive jobs.
Versatility means the ability to adapt or be adapted to many different functions or activities. We can use a computer to perform completely different types of work at the same time.
The computer seems capable of performing almost any task efficiently, provided that task can be broken down to a series of logical steps, and provided to the computer in the way, that it can understand.