Input Devices Used in Computing

Input and output devices comprise hardware that makes it possible for a user to interact with the computer. They function differently in that; input devices allow an individual to feed instructions to the computer and receive the processed results through output devices. Therefore, data input precedes data output. Nonetheless, it’s important to note that computers work solely with digital information, thus, make sure you digitize all the information before you input it to the machine. For instance, if you connect a flash disk to your computer to play an audio file, all the processes involved from the moment you insert the flash disk are inputs. Opening a folder, scrolling down to select the particular file, loading the player and playing the music you want is all part of feeding the computer with instructions so that it can process them and provide you with an output in the form of sound. Some of the most common input devices include microphones, mouse, webcam and keyboards. This article examines a few of the input devices most commonly used, their functions and how they work.


A mouse is a tiny semicircular device that comes with a flat bottom and curves that fit into the palms of your hands. The movement of the cursor on the screen is dictated by the physical motion of the mouse as moved by the user. The mouse makes one of the most basic input devices when it comes to computing. The importance of the mouse can be underlined by the fact that the operating system and all programs are designed in such a way that they can only be navigated or controlled using this device. However, when using a laptop computer, rather than the small object you move with your hands, the mouse is replaced with a flat panel operated using a finger that tends to be sensitive to pressure.


The keyboard is a flat panel that is fitted with several rows of keys. The keys are labeled on top with alphanumeric letters and numbers as well as a set of other special keys that have unique functions. It is equally as important as the mouse when it comes to feeding the computer with instructions. In the absence of a mouse, the keyboard can assume some duties of the mouse through keyboard shortcuts. For example, pressing Alt simultaneously with F4 automatically closes any open window. Typically, most users use the mouse to close any open windows. Keyboards also come as concept keyboards whereby, every key relates to a particular function or item. Depending on the setting where it is being used, the keys can be labeled with images or texts. For instance, in a fast food restaurant, a concept keyboard will have the buttons labeled with names or pictures of different meals making it easy to order a particular meal just by pressing the button.


Microphones are used widely in various settings and applications including public address systems, telephones, sound recording, television and radio broadcasting, as well as to record voice in computers. Other devices such as webcams or gaming headphones come with inbuilt microphones. Nonetheless, others are used with voice recognition software and word processing applications to convert voice input into text. Microphones transform sound into an electric signal and come in different types. They are differentiated mostly by the manner in which they convert air pressure variations of a sound wave to an electrical signal. Some of the models available in the market include the condenser microphone, dynamic microphone, and the piezoelectric microphone. Besides, a microphone can also be characterized based on its intended use, directional characteristics and other factors such as the diaphragm size. You can read more about the different types of microphones on the numerous online sources and learn how to choose the best depending on your personal needs.


As noted earlier, computers only work with digitized information. As such, scanners are used to optically convert images, handwritten text or printed text into digital images so that they can be stored, shared or sent through a computer. They work in the same way as photocopiers, only that they produce digital copies rather than physical copies. The signal sent from a scanner is converted into a digital image that can be edited, printed or even stored as a soft copy. By using particular software, you can convert the scanned image into other formats such as PNG or JPEG. Scanners come in different types including hand scanner, a desktop scanner, and rotary scanner. All these kinds work differently, and each one of them has its advantages and disadvantages. In the modern day, people are making use of digital cameras in place of scanners. Unfortunately, the image is often distorted to some extent and may include shadows and reflections making it appear blurred.

Digital Cameras

With the advent of smart phones and other android devices, people no longer need to carry around cameras. These devices have digital cameras that can take clear pictures as well as record videos. The images that you take or the videos you record are stored in files that you can easily transfer to a computer for editing, storage, or printing. These devices come with USB cables that allow the user to copy the files from his phone or camera to a computer directly.


Trackballs are input devices used as an alternative to a mouse. It operates in the same way as the mouse whereby the user rotates the ball, and it moves the pointer or cursor on the screen. They are quite easy to operate and have more precision compared to a mouse. Therefore, they make an excellent choice for individuals with limited hand movements and are also often used in Computer Aided Design.

Video Digitizer

Some people have the tendency of converting an image from a TV or a video camera and converting it into a digital version. A video digitizer comes in handy for that purpose making it possible to read and store such an image on a computer. If you have a multimedia presentation you need to make; this device can come in handy to capture all the video sequences you need.

Barcode reader

Barcodes are characterized by black vertical lines of varying thickness and are decoded by a barcode reader. These codes are unique, and you will find them in almost every product you buy in a department store or a supermarket. A barcode represents varying information about the product you want to buy including the name and the price, which happen to be displayed on the receipt. Also, a barcode reader helps in keeping track of the stock as every time you scan a product; it gets deducted from the inventory.

Overall, both input and output devices are necessary for the computing process. Whether you are using a mic to input voice or a scanner to convert text and images into digital forms, it is important to know which devices are ideal for which tasks. The information highlighted in this article will be a good starting point and a guide to help you understand how to digitalize your information.