Computer system
AS YOU start a new academic year, you are encouraged to refocus, work harder and stay committed in order to achieve your academic goals.
Please be advised that the information technology syllabus has been revised and the students who will be going into fourth form will now be taught the new syllabus and will be the first to sit an exam based on the new syllabus in May/June 2020. The Youthlink lessons for IT will be geared towards the current grade-11 students, and will be based on the old syllabus to reflect their CSEC exam that they will sit in May /June 2019.
Our initial lessons will be focusing on Section 1: Fundamentals of Hardware and Software of the syllabus. This is lesson one in our series. In this lesson, we will be looking at the terms ‘computer’, ‘system’ and main components of a computer system.
A computer may be defined as an electronic device which accepts input (instructions, commands, data, etc), processes the input and produces results (output) from the processing, and stores data and results for future use.
Let us first examine one of the possible inputs you may enter in a computer; that is data.
Data is a set of raw facts and figures that a computer processes by following a set of instructions called a program, while information is the processed data which is meaningful and useful.
The main components of a computer system are: hardware, software and the user. Hardware – This is the name given to the physical parts of a computer that you can see and touch. Some of these hardware components may be referred to as peripherals. Peripheral devices are any external devices or components connected to the system unit, such as a mouse, keyboard, printer, monitor, etc.
The system unit is the box-like case that houses all the electronic components of the computer.
There are five general categories of hardware, namely:
input devices – they get data, instructions or commands into a computer for processing. A mouse, keyboard, touch screen, joystick, biometric systems and a scanner are all examples of input devices.
The central processing unit (CPU) – this is the brain of a computer, also called the microprocessor, and it controls how the rest of the computer works. It is assisted by the control unit (CU) and the arithmetic logic unit (ALU). The CU carries out instructions in the software and directs the flow of data through the computer; the ALU performs the calculations and logic operations.
Output devices – they get processed information out of a computer, for example to a printer, monitor or even speakers.
Storage devices – include floppy diskettes (even though there are not used anymore), hard disk drives, flash drives, compact disc (CD) ROM drives and so on, that are used for storing information permanently.
Memory enables a computer to temporarily store instructions and data, for example, the RAM chip (which you will learn more about when we look at storage). Below is a diagram which illustrates the input-processing-output-storage cycle (IPOS) of a computer system similar to the picture above.