Introduction
Computer is a machine that can be programmed to accept data (input) process it into useful information (output) and stored it away (in a secondary storage device) for safekeeping or later reuse. The processing input to output is directly by the software but performed by the hardware.
To function, a computer system requires four main aspect of data handling:
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Input
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Processing
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Output
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Storage
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Secondary Storage
Input ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Processing ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Output
Figure 1.1 the hardware responsible for these four areas
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Input devices accept data or commands in a form that computer can use; they send the data or commands to the processing unit.
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ The processor; more formally known as Central Processing Unit (CPU); has electronic circuitry that manipulates input data into the information people want. The Central Processing Unit actually executes computer instructions.
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Output devices show people the processed data-information-in understandable and usable form.
ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ ÃÂÃ Storage usually means secondary storage, which consists of secondary storage devices such as disk-hard disk or diskettes or some other kind of disk-that can store data and programs outside of the computer itself. These devices supplement memory or primary storage, which can hold data and program only temporarily.
Input: Getting data from the user to the computer
Some input data can directly to the computer for processing. Input in this category includes barcodes, speech that enters the computer through a microphone, and data entered by means of a device tat convert motions to one screen action. Some input data, however, go through a good deal of intermediate handling, such as when it is copied from a source documents (jargon of originally written data) and translated to a medium that a machine can read, such as a magnetic disk. In either case the task is to gather data...