A computer is a machine that can be programmed to manipulate symbols. Its principal characteristics are:
- It responds to a specific set of instructions in a well-defined manner.
- It can execute a prerecorded list of instructions (a program).
- It can quickly store and retrieve large amounts of data.
Therefore computers can perform complex and repetitive procedures quickly, precisely and reliably. Modern computers are electronic and digital. The actual machinery (wires, transistors, and circuits) is called hardware; the instructions and data are called software. All general-purpose computers require the following hardware components:
- Central processing unit (CPU): The heart of the computer, this is the component that actually executes instructions organized in programs (“software”) which tell the computer what to do.
- Memory (fast, expensive, short-term memory): Enables a computer to store, at least temporarily, data, programs, and intermediate results.
- Mass storage device (slower, cheaper, long-term memory): Allows a computer to permanently retain large amounts of data and programs between jobs. Common mass storage devices include disk drives and tape drives.
- Input device: Usually a keyboard and mouse, the input device is the conduit through which data and instructions enter a computer.
- Output device: A display screen, printer, or other device that lets you see what the computer has accomplished.
In addition to these components, many others make it possible for the basic components to work together efficiently. For example, every computer requires a bus that transmits data from one part of the computer to another.
|Characteristics of computer|
1. SPEED : Computer is very fast calculating device. It can execute basic operations like subtraction, addition, multiplication and division at a few microseconds. It can move and copy data at a speed in the order of billion instruction per second.
2. ACCURACY : Computer always gives accurate results. The accuracy of Computer does not go down when they are
used continuously for hours together. It always gives accurate results.
3. STORAGE CAPACITY : Computer have a very large storage capacity. A large volume of information can be stored in the memory of computer and information can be retrieved correctly when desired.
4. VERSATILITY : The working of computer with different types of data is known as versatility. That means computer can perform different types of job efficiently. Computer can works with different type of data and information such as visuals, text, graphics & video etc. So, versatility is a most important characteristic of computer.
5. DILLIGENCE : A Computer can work for long hours with the same accuracy and speed because it is free from problems of boredom or lack of concentration.
6. NO THOUGHTS : Computers have no thoughts because they are machine and they are devoid of emotions. They have no feelings. Since, computers have no thoughts and feelings so they can’t make judgment based on thoughts andfeelings.