Input And Output Devices

• An output device is any piece of computer hardware equipment which converts information into human-readable form.

• Monitors
• Printers
• Plotters
• Motors
• Buzzers
• Lights 
• Heaters

Printing and plotting is a way to get a physical/hard copy of data that has been recorded on a computer.

In the past, it was normal for most people to use a Dox Matrix Printer in order to get a physical copy. Dox Matrix Printers use inked tiny pins to hit the paper in order to create patterns that become numbers, letters and images. The cost of the printer and operating costs are very low, making it a good option however, the quality of the printouts are very low and the printer is very noisy while operating

After some time, the Inkjet Printer was created. This printer is very similar to the Dot Matrix Printer but instead of using tiny pins, it squirts coloured ink onto the paper to create an image, making it perfect for photographs. These printers are relatively cheap and quite however, the cost of the ink is high.

The common printer today is called the Laser Printer. The most complex printer to be made so far. The cost of the printer is quite high however, the cost of using it is low as it uses a dust called toner. This printer uses lasers to stick the toner onto the paper in order to create images, text and numbers. 

Plotters are completely different in comparison to the other printing devices. Plotters basically use a pen to draw the images and texts. The pens are held by a robotic arm that is able to draw more quickly and accurately than a human. Plotters are ideal for designers and architects.

For the visual aspect, the most common devices are monitors and projectors while for the audio, it's mostly speakers.

The first stable monitor was the Cathode Ray-Tube Monitor (CRT). This is the classic block like monitor that takes up most of the space on a desk. 

In the modern times today, most people use a flat screen monitor. These monitors are lightweight, don't take up too much space and most importantly, they show a much clearer picture with better brightness and colour accuracy. These monitors have completely replaced the CRT Monitors.

Although monitors are great, projectors are more optimal for situations such as presentations, advertising and watching movies. Projectors are very similar to monitors as they both connect to computers, DVD players and satellite receiver to work. The projectors are able to "project" the images or videos onto flat walls or other objects.

Music, sound effects and just sound in general have to come out from a loudspeaker. This device converts electrical sound into sound waves which can be heard by us humans.

A regular computer is not able to change the environment around it by itself. In order for them to do so, actuators need to be used.

An actuator is a device that can change things in real life while being controlled by computers.

Here is a list of some actuators and a brief description of what they can do:

• An input device is a piece of equipment used to provide data and control signals to an information processing system such as a computer or information appliance.

• Remote Controls
• Joysticks
• Touch Screens
• Magnetic Stripe Readers
• Pin Pads
• Cameras
• Microphones
• Sensors
• MICR
• OMR
• OCR

Devices like scanners are used to scan images, book pages and more. Scanning is essentially just taking a very detailed photo and transferring the data to the computer.

Other devices such as digital cameras captures digital photographs while video cameras capture moving images/videos.

For audio, microphones convert sounds into a signal that the computer can be given to the computer. These signals are normally analogue, so it has to be converted to digital using an Analogue to Digital Converter which can be read to the computer.

Card readers are devices that are designed to read data that are stored within cards such as credit cards and smart cards, the data is stored in the form of magnetised dots, these dots are kept in a magnetised strip. Card reading devices such as a magnetic strip readers can read the strips and interpret the data much faster than a person typing it in. The way it works is that the users should swipe their card through the slot and the data should be interpreted.

Other than magnetic strip readers, smart card/chip readers can also be used in the same way. Some cards use ID chips instead of magnetic strips and that's why these devices were made. These chips have an embedded computer memory device in which data can be stored. The smart card/chip readers are able to interpret the data from the chips.

Scanners and readers can be used in many ways and for many purposes. Scanners are used to mark examination papers in many countries. Devices like OMR scanners are designed to mark multiple choice questions in exams. This devices is able to read spaces that have colour in them. While a device like an OCR scanner is able to turn real life written words into text files which can then be marked.

Banks use MICR readers to interpret cheques. This is possible because this device is able to read a special font that is written using a special magnetic ink. MICR readers are able to interpret data quickly and accurately.

It is very normal to see supermarkets use a bar code reader at their checkouts. They are used to increase efficiency for checking out. These bar code readers are able to read numeric codes that are represented by a series of lines

Normal computers are unable to see what is happening around them but this can be solved by using specific sensors. 

Example of these sensors are:

1. Temperatures sensors
2. Light sensors
3. Pressure sensors
4. Moisture sensors
5. Water level sensors
6. Movement sensors
7. Proximity sensors
8. Switch/Button sensors