Input and output devices

The operation of a computer system is based on the combined use of input and output devices. Through the former, we can instruct the computer to perform an action and the device returns to our action through an output device. In this article, we will discuss the various input and output devices that can be connected to a computer, along with their functions.

What are input and output devices

Definition of input device: A piece of equipment / hardware that helps us enter data into a computer is called an input device. For example, keyboard, mouse, etc.

Output device definition: a piece of equipment / hardware that is the result of an input entered, once it is processed (i.e. converts data from machine language to human-understandable language), it is called a device output. For example, printer, monitor, etc.

Examples of input devices

Below is the list of the most common input devices along with brief information about each of them.

1. Keyboard

The keyboard is a simple device that contains keys with the letters of the alphabet, numbers, and commands that can be given to a computer to perform various actions. It would be like a modified version of the typewriter. This  is an essential input device and both desktop and laptop computers use it to give commands and actions to follow.

2. Mouse

Also known as a pointing device . Through the use of it, we can click directly on the various icons present in the system and open various files and programs. A mouse consists of 3 buttons on the top and a trackball or saler on the bottom, which helps to select and move the mouse, respectively. In the case of laptops, the touchpad is provided as a replacement for the mouse, which aids the movement of the pointer.

3. Joy Stick

It is a device that consists of buttons and levers, and is mainly used to control movement in video games. In addition to being used in computer systems, they can also be found, for example, in the cabin of an airplane, in electric wheelchairs, in cranes, trucks, etc.

4. Digital pen

It is a device with the appearance of a pencil or wand that can be moved directly on the screen of the device. It is sensitive to light and is used in conjunction with your computer’s cathode ray tube.

5. Microphone

Through the use of a microphone, sound can be stored on a device in its digital form. It converts sound into an electrical signal . To record or play a sound created with a microphone, it must be connected to an amplifier.

6. Scanner

This device can scan images or texts and convert them into a digital signal. When we put any part of a document on a scanner, it converts it into a digital signal and displays it on the computer screen.

7. Barcode reader

It is a kind of optical scanner that is used to read barcodes . A light source passes through a barcode and its aspects and details are displayed on the screen.

8. Webcam

It receives images generated by whatever is pointed (input) and sends them to a computer.

9. Graphic tablet / digitizer

It consists of a flat board and a pointing device , known as a pencil, which allows the user to enter data in much the same way as using a pencil and paper. These work in many different ways.

Graphic designers often use them to produce illustrations, such as designing a logo. Of course, this is also used on tablets as the main input device.

The main factors affecting its performance are its resolution, measured in lines per inch (LPI), and its pressure sensitivity. The pressure sensitivity allows a greater range of pressure to be detected, from a light touch to a strong touch.

10. Sensor

The sensor is an input device that takes readings from the environment, such as temperature, light, and motion . Obviously, each type of sensor works completely differently. An example of where this could be used is on a thermostat that senses the temperature and turns the heat on or off.

All the devices mentioned above are the most widely used input devices. Various other types of equipment of this type are used in different fields that can be counted as an input device.

Examples of output devices

The most commonly used output devices are listed below with a brief summary of what their function is and how they can be used.

1. Monitor

The device that displays all icons, text, images, etc. on a screen it is called a Monitor. When we ask the computer to take an action, the result of that action is displayed on the monitor . Over the years, various types of monitors have been developed.

2. Printer

A device that makes a copy of pictorial or textual content , usually on paper, is called a printer. For example, an author writes the entire book on his computer and then gets a hard copy on paper. There are also several types of printers available in the market, which can serve different purposes.

3. Speakers

A device through which we can hear sound as a result of what we command a computer to do is called a speaker / speaker. These are connected to a computer system and are also a hardware device that can be connected separately. With the advancement of technology, there are speakers that are wireless and can be connected using BlueTooth or other applications.

4. Projector

An optical device that presents a moving image or images on a projection screen is called a projector. They are typically used in auditoriums and cinemas for video display or lighting. If a projector is connected to a computer, then the image / video displayed on the screen is the same as the one displayed on the pc screen.

5. Headphones

They perform the same function as a speaker, the only difference is the frequency of the sound . Using speakers, the sound can be heard in a larger area and using headphones, the sound is only audible to the person using them . Also known as headphones or earphones

6. Solenoid

It is an output device that produces movement and that we use to control or move things . They are commonly used with sensors as part of ‘Ubiquitous Computing’ devices. An example could be an actuator that turns our heating on or off. There are different types of actuators that produce different movements and that can affect performance measures.

7. Plotter / Plotter

A plotter is an output device that prints high-quality graphic images in many color formats . It is similar to a printer, but has more advanced features with more accurate, faster, and high-resolution graphics. It enables you to print large maps, architectural drawings, 3D postcards, billboards, graphics, large format printing, and various designs of the internal structure of buildings or machines. That is why tracers are widely used in fields such as engineering and architecture, where precision is a must.

8. Video cards

These are hardware devices that work in conjunction with the monitor to display visual output to the user . This hardware device also helps the user to return information to the computer, thus improving interaction. In turn, it processes the images seen on the monitor and determines their return quality.

9. Sound cards

Although a video card is an essential component of a computer, as it works with the monitor for good display development, a sound card is optional. Also, this output device brings you a better user experience. However, just like the video card, a sound card also determines the quality of the sound produced by a computer’s speakers, whether internal or external . In addition, sound cards are primarily used by sound engineers, music producers, and multimedia creators for smooth and good sound productions.

10. CD and DVD reader / writer

These have become standard output devices for computers. The advantage of these output devices is that they store data for a long period of time. CDs and DVDs can be burned to share information.