Information Technology Fundamentals – System Components
A computer is a digital machine that, when instructed by a computer programme, can carry out a variety of mathematical and logical operations.
The following are the five most important components of a computer system:
- Input Devices
- Output Devices
1. Input Devices
A user's ability to input information and commands into a computer is facilitated by input devices. A computer's Central Processing Unit (CPU) takes in data, processes it, and returns the computer's output.
Common input devices include:
The keyboard is used to enter data into a computer or other electronic device by pressing keys. There are distinct groups of keys for letters, numbers, special characters, and functions. For wireless communication, keyboards are connected to a computer through USB or a Bluetooth device.
Depending on the region and language, there may be a variety of keyboard types. Common types of keyboards include the following:
First, the QWERTY keyboard: Nowadays, this type of keyboard is the standard for use with computers. Its popularity extends to countries whose native alphabets do not use the Latin script, hence its name, which is derived from the first six buttons on the device's top row. Since it has become so commonplace, some people may mistakenly believe that there is no other keyboard suitable for use with computers.
AZERTY Keyboard: It is the standard French keyboard layout. It was created in France as an alternative to the QWERTY keyboard layout and is primarily employed in France and other European countries. Some nations have developed their own AZERTY keyboards.
It derives its name from the first six letters on the top left row of the keyboard. The Q and W keys of the AZERTY keyboard are swapped with the A and Z keys of the QWERTY keyboard. In addition, the M key is located to the left of the L key on an AZERTY keyboard.
The AZERTY keyboard differs from the QWERTY keyboard in more ways than just letter placement; for instance, it emphasizes accents, which is necessary for writing European languages such as French.
Thirdly, a DVORAK keyboard: This keyboard layout was created to increase typing speed by reducing the amount of finger movement required while typing. To improve typing, the most frequently used letters are kept in a home row.
The mouse is a handheld input device used to move the pointer or cursor across the display. It is intended for use on a flat surface and typically consists of left and right buttons and a scroll wheel. Laptops include a touchpad that functions as a mouse. You can control the movement of the cursor or pointer by dragging your finger across the touchpad. Some mice include integrated features, such as additional buttons for performing various functions.
1963 saw the invention of the mouse by Douglas C. Engelbart. Early mice incorporated a roller ball as a movement sensor beneath the device. Optical technology is incorporated into contemporary mouse devices to control cursor movement with a visible or invisible light beam. Depending on the type of computer and mouse, different ports are used to connect a mouse to a computer.
A joystick, like a mouse, is a pointing input device. It consists of a stick with a sphere-shaped base. The base is mounted in a socket that allows the stick to move freely. The movement of the analogue stick controls the on-screen cursor or pointer.
C. B. Mirick invented the first joystick at the U.S. Naval Research Laboratory. There are numerous types of joysticks, including displacement joysticks, finger-operated joysticks, hand-operated joysticks, and isometric joysticks. In joystick, the cursor continues to move in the direction of the joystick unless the joystick is upright, whereas in mouse, the cursor only moves when the mouse moves.
A light pen is an input device for computers that resembles a pen. The light-sensitive detector at the tip of the light pen enables the user to point to or select objects on the display screen. Its light-sensitive tip detects the location of an object and transmits the appropriate signals to the CPU. Because it is incompatible with LCD screens, it is no longer utilized. It also allows you to draw on the screen when necessary. The first light pen was invented around 1955 at the Massachusetts Institute of Technology as part of the Whirlwind project (MIT).
A digitizer is a computer input device with a flat surface and typically a stylus. It allows the user to draw images and graphics with the stylus, similar to how we draw with a pencil on paper. The images or graphics drawn on the digitizer are displayed on the monitor or display screen of the computer. The software transforms touch inputs into lines and can convert handwritten text into typed words.
It can capture handwritten signatures, data, and images from taped documents. In addition, it is used to receive data in the form of drawings and send output to CAD (computer-aided design) applications and software such as AutoCAD. Therefore, it permits the conversion of hand-drawn images to a format suitable for computer processing.
Optical Character Reader (OCR)
OCR input devices are designed to convert scanned images of handwritten, typed, or printed text into digital text. It is commonly used in offices and libraries to digitize documents and books.
Using a scanner, it processes and duplicates the physical form of a document. After duplicating the documents, the OCR software converts them into a two-color (black and white), bitmap version. The image is then analyzed for light and dark areas, with the dark areas identified as characters and the light areas as background. It is commonly used to convert paper legal or historical documents to PDF format. The converted documents can be edited if necessary in the same manner as Microsoft Word documents.
It is a digital device because it digitally captures images and records videos, which are then stored on a memory card. As opposed to traditional cameras, it utilises an image sensor chip to capture images. A camera that is connected to a computer can also be referred to as a digital camera.
It has photosensors for capturing light that enters through the lens. When light hits the photosensors, each sensor returns an electrical current that is used to create images.
2. Output Devices
The output device displays the result of the computer's processing of raw data entered via an input device. There are various output devices that display output in various formats, including text, images, hard copies, audio, and video.
Some popular output devices include:
- CRT Monitor
- LCD Monitor
- LED Monitor
- Plasma Monitor
- Impact Printers
A. Character Printers
i. Dot Matrix printers
ii. Daisy Wheel printers
B. Line printers
i. Drum printers
ii. Chain printers
- Non-impact printers
A. Laser printers
B. Inkjet printers
The monitor is the computer's visual display unit. It is the primary means through which the processed data or information is communicated to the user, be it in the form of text, images, audio, or video.
A printer makes physical copies of the data that has been processed. It permits the user to print images, text, and other data onto paper.
Impact Printers and Non-impact Printers are the two types of printers based on the printing mechanism.
- Impact Printer: The impact printer prints characters or graphics onto paper using a hammer or print head. To print characters and graphics, the hammer or print head strikes or presses an ink ribbon on the paper.
- Non-impact Printer: If you're looking for a printer that doesn't use a print head and hammer to transfer information to paper, look no further than a non-impact printer. Characters and images are printed without the paper ever coming into contact with the actual printing equipment. These printers are also referred to as page printers due to their capability to print entire pages. Inkjet printers and laser printers are the most common forms of non-impact printers.
A projector is a type of output device that allows the output to be projected onto a large surface, like a wall or screen. It's compatible with computers and other devices, so you can display what they're showing on a big screen. Through the use of light and lenses, it is able to enlarge printed materials, digital photos, and video. As a result, it is a great tool for teaching or presenting to a wide audience.
Today's digital projectors handle a wide variety of input formats, including HDMI for the newest devices and VGA for the most often used ones. A few models of projectors are built with wireless networking and auxiliary inputs in mind. They are widely used in schools for lectures, presentations, home theatres, etc., and can be mounted on the ceiling, set on a stand, or employed in a variety of other ways.
3. Central Processing Unit (CPU)
A CPU may also be referred to as a central processor, microprocessor, or just a processor. All the main computer tasks are executed by it. It takes input from both the hardware and the currently running programme and processes it to generate the desired results. All of the system and application software is kept there. The CPU also facilitates communication between I/O devices. This is why the central processing unit (CPU) is sometimes referred to as the "brain" of a computer.
The central processing unit (CPU) is fitted into the motherboard's CPU socket. In addition, a heat sink is included to help remove excess heat and maintain optimal CPU performance.
Generally, a CPU has three components:
- ALU (Arithmetic Logic Unit)
- Control Unit
- Memory or Storage Unit
HW, which is an abbreviation for hardware, refers to all physical components of a computer system, including any associated devices. Without hardware, you cannot make a computer or use software. The display on which you are viewing this text is also hardware.
Software (abbreviated as SW or S/W) is a collection of programmes that enables the hardware to do a certain task. All computer programmes are considered software. System software, application software, and programming software are three categories of software.