According to Guvava N and Madziwo E.T, “A computer is an electronic machine that accepts information, stores it until the information is needed, processes the information according to the instructions provided by the user, and finally returns the results to the user. The computer can store and manipulate large quantities of data at very high speed, but a computer cannot think.” Another related definition according to Loudon and Loudon, 2007, “a business information system is a group of interrelated components that work collectively to carry out input, processing, output, storage and control actions in order to convert data into information products that can be used to support forecasting, planning, control, coordination, decision making and operational activities in an organization.”
A computer has 2 main parts: hardware, software. The physical equipment associated with a computer system is called the hardware. Software relates to the set of instructions that instructs the hardware how to behave. To be specific a software is program, while a program is a set of step-by-step instructions that directs the computer to do the tasks you the user wants or intends to do.
According to Guvava N and Madziwo E.T ,”This refers to the physical components of a computer. These are the parts that you can see, feel and hear on a computer. Examples are the central processing unit, the keyboard, the monitor, memory, cables, mouse, printer and speakers”. Also, according to Elizabeth Hardcastle, “Hardware describes the physical components of a computer system which can be categorized as input devices, a central processing unit, internal and external memory and output devices.” A computer can be programmed to accept data (input), process it into information (output), and to be stored away or later reuse. Processing of input to output is controlled by the software but executed by the hardware.
Input devices accept data or instructions from outside the computer, in a form that the computer can assimilate; the data is then sent to the processing unit. A keyboard, joystick, sound card and a mouse are examples of input devices. While the input itself is the data put into the computer system for processing. Examples of putting input data into the computer are: Pointing with a mouse. As one moves a mouse is a by hand over a flat surface, the movement causes corresponding movement of a pointer on the computer screen. While pressing buttons on the mouse invokes commands. Typing on a keyboard. The computer responds to what is entered on the typing pad; i.e., it “echoes” what is typed by displaying it on the screen.
Central Processing Unit
The processor, more formally known as the central processing unit (CPU), has the electronic circuitry that manipulates input data into the information people want. The central processing unit executes computer instructions that are specified in the program. The central processing unit consists of electronic circuits that interpret and execute program instructions, as well as communicate with the input, output, and storage devices. The more memory and disk storage a CPU have, the more processing it can handle within a given amount of time, and the faster it can complete a task. The CPU has 3manin parts which are: the control Unit, the Immediate Access Store and the Arithmetic and Logic Unit (ALU).
It is the central processing unit that transforms data into information. Data is the raw material to be processed by a computer. Such material can be letters, numbers, or facts like grades in a class, baseball batting averages, or light and dark areas in a photograph. Processed data becomes information, data that is organized, meaningful, and useful. In school, for instance, an instructor could enter various student grades (data), which can be processed to produce final grades and perhaps a class average (information).