2 Input and output devices

Keyboard

Used for inputting data into applications and typing commands into a CLI Interface. It is easy and familiar to use and allows fast entry of text into a document, but is a slower method compared to direct data entry.

Numeric Key Pad

Used for inputting numeric data into ATMs, POS Terminals, Chip and Pin, and Mobile Phones. It is straightforward to enter numeric data like pins or prices at a POS, but keys can be too small and it is difficult to type letters.

Mouse

Used to control the pointer on the screen for selecting windows, clicking icons, menu options, and positioning the pointer. It is easy to navigate through menu options and quicker to select an option compared to using a keyboard, but is easily damaged and requires a flat surface.

Touch Pad

Used as a pointing device on a laptop. It is part of the keyboard so there is no need for a separate device, but it is more difficult to use compared to a normal mouse.

Tracker Ball

Used by users who tend to have limited motility in their wrist (RSI). It is easier to use compared to a mouse and offers more accurate positioning of the pointer, but tends to be more expensive and is not familiar to users.

Remote Control

Used to control TV channels, menu options, multimedia systems, and industrial applications. It can be used from a distance, but the signal could be blocked by obstacles or walls.

Joystick

Used in computer games and simulators. It is easier to use compared to a keyboard, but more difficult to use compared to a normal mouse.

Driving Wheel

Used by gamers in computer games (Racing/Driving) and in simulators. The driving experience is more accurate than using keyboards, but it is more expensive and movement could be too sensitive.

Touch Screen

Used on Mobile/Tablets, Point of Sale (POS), and Interactive White Boards. It is very easy to use and select options, but options could be selected accidentally and the screen can get dirty.

Scanners

Used to scan in documents or photographs. Copies can be created, but quality is dependent on resolution settings.

Digital Cameras

Used to take photographs and small video clips. Data can be transferred to computers, higher resolution images can be stored on memory cards, and there is no need to develop film, but transferring, storing, and editing images can be complicated.

Video Cameras

Used to record video footage. It can record in HD and footage can be edited on a computer, but HD movies take up a lot of storage and the camera is costly.

Microphone

Used to input sound into a computer and in voice recognition applications. Voice overs can be added to presentations and recorded audio can be typed directly into Word Processor applications, but voice recognition is not as accurate as typing text.

Graphics Tablet

Used with a stylus to draw free hand drawings which can be stored on a computer. It is a very accurate method of drawing compared to a pointer device, but it takes longer to produce drawings and the tablet is expensive.

Web Cams

Used by users who want to have a web conference (Skype Call). It allows for face to face video chat and contact with people without the need to travel, but quality is dependent on internet connection.

Light Pens

Used in CAD applications for drawing onscreen. It is more accurate than touch screens and small in size, but only used with CRT Monitors and is dated technology.

Sensor

A device that converts a real world property into data that a computer can process. Examples include Temperature, Light, Moisture, Water-Level, Proximity, Movement, and Pressure.

ADC (Analogue-to-digital converter)

Real world measurements are collected as an analogue signal from the sensor. A computer only understands digital signals, so an ADC is needed to convert the signal so a computer understands it.

Magnetic Strip Reader

Used to read data on bank cards, arcade cards, security/hotel rooms, and gift cards It allows fast data entry, is secure/error-free, is not affected by water, and is easily updated; however, the stripe could become unreadable if scratched, it does not work at a distance, and cards are easily lost.;

Chip and Pin Reader

Used at POS terminals to make secure payments. It is a secure method compared to swipe and contactless, and the chip is less likely to be damaged than a magnetic stripe, but the pin could be read by someone watching and fraudulent machines can copy details.

Contactless Cards Reader

Used to pay for products without a PIN using RFID technology. The payment terminal picks up a signal from the chip to process the transaction when the card is within a few centimetres. It is quicker than PIN methods, but anyone could use the card if lost and it is easier for thieves to copy details.

RFID (Radio Frequency Identification)

Reads information stored on tags using radio waves to track animals, stock, or luggage. It can read objects from a distance and in bulk very fast, but radio symbols can be jammed or hacked and tags are more expensive than barcodes.

MICR (Magnetic Ink Character Reader)

Used to process bank cheques. Characters printed in special ink are converted into a form understood by the computer. It eliminates manual entry errors and characters cannot be altered or obscured by writing, but it is expensive and reads a limited amount of characters.

How MICR Reads Cheques

The magnetic ink on the cheque passes over a magnet in the MICR. The MICR then reads the magnetic signal given out by the magnetic ink characters. Each character produces a unique signal which is read and translated by the MICR.

OMR (Optical Mark Reader)

Used to scan marks from multiple choice exams, surveys, and lottery tickets. It is a very fast and accurate method of inputting data, but forms must be completed correctly to avoid time-wasting manual checks.

OCR (Optical Character Reader)

Used in self-immigration systems, ID cards, and scanning text for editing. It is faster than manual typing and has less chance of errors, but is not as accurate as OMR and cannot read handwriting.

Barcode Scanner

Used at POS to scan codes containing unique product information. It is quicker and more accurate than manual typing and allows easy price updates, but barcodes can be unreadable, missing, or swapped.

QR (Quick Response) Scanners

Often used in advertising (scanning a code on a poster to visit a website), restaurant menus, and event tickets. Advantages: Can hold much more data than a standard barcode. can be read from different angles. small and easy to print. Disadvantages: Requires a smartphone or a camera with specific software; can be used by hackers to direct users to "malicious" websites (Link squatted/faked).;

CRT (Cathode Ray Tube) Monitor

Used as primary output display. It is cheaper than other monitors and can be used with light pens, but is bulky and requires more desk space.

LCD (Liquid Crystal Display) Monitor

Primary output for computers and monitors. It is smaller, lighter, consumes less power, and generates less heat than CRT, but resolution may not be as good.

LED (Light-Emitting Diode) Monitor

Used in store signs and billboards. It produces better light for improved colour definition, is energy efficient, and works well in different light, but is more expensive.

IPS (In-Plane Switching) Monitor

Used by creative professionals. It has wide viewing angles and better colour reproduction, but is more expensive.

Multimedia Projector

Used in classrooms and training to project signals onto a large screen. It allows more people to see the output, but resolution may be lower and obstacles can block the projection.

Inkjet Printer

Used for low output volumes like home homework. It offers cheap high quality printing and takes up less desk space, but ink cartridges run out quickly and printing is slow.

Laser Printer

Used for high output volumes in schools and offices. It offers high quality, fast, and quiet printing with long-lasting toner, but the printer itself is more expensive.

Dot Matrix Printer

Uses a print head against an inked ribbon for shop receipts or carbon copies. It is not affected by hot/dusty environments and is cheap to maintain, but is very slow, noisy, and poor quality.

Wide Format Printer

Used for banners, billboards, and posters. It offers high resolution large printouts, but is expensive to buy and maintain.

Plotter

A specialized output device that uses pens to draw continuous, high-precision vector lines for CAD, blueprints, and engineering drawings.

3D Printer

Produces solid objects by building layer upon layer for prosthetics or manufacturing. Products can be customized and prototypes created quickly, but the printer and materials are very expensive.

Speakers

Required to output sound for movies or games. They can be used wirelessly and sound can be amplified, but they are not as personal as headphones.

Actuator

Part of the control process where digital signals are sent by the computer to affect the real world. Examples include Motors (washing machines), Buzzers (burglar alarms), Heaters (ovens), and Lights (security lights).