Input device

An input device is any hardware device that sends data to a computer, allowing you to interact with and control it. The picture shows a Logitech trackball mouse, which is an example of an input device.

The most commonly used or primary input devices on a computer are the keyboard and mouse. However, there are dozens of other devices that can also be used to input data into the computer.

An input device is a piece of hardware used to provide data to a computer used for interaction and control.  It allows input of raw data to the computer for processing.
Here’s a list of some input devices used in computers and other computing devices:

• Keyboard – one of the primary input devices used to input data and commands. It has function keys, control keys, arrow keys, keypad and the keyboard itself with the letters, numbers and commands.  Keyboards are connected to the computer through USB or Bluetooth.  A laptop keyboard is more compact than a desktop keyboard to make the laptop smaller and lighter.  Smartphones and tablets use on-screen keyboard to input messages and select commands.
• Mouse – an input device used to control the cursor and coordinates. It can be wired or wireless.  It allows the user to do the following:

·         Move the mouse cursor

·         Select

·         Scroll

·         Open or execute a program

·         Drag-and-drop

·         Hover

·         Perform other functions with the use of additional buttons

·         A laptop uses a touchpad as the mouse.  A smartphone and tablet use a touchscreen as primary input device and the user’s finger is used as the mouse.

• Microphone – an input device that allows users to input audio into their computers. Here are some uses of the microphone:

·         Audio for video

·         Computer gaming

·         Online chatting

·         Recording musical instruments

·         Recording voice for dictation, singing and podcasts

·         Voice recorder

·         Voice recognition

·         VoIP – Voice over Internet Protocol

• Digital Camera – is an input device that takes pictures digitally. Images are stored as data on memory cards.  It has an LCD screen that allows users to preview and review images.  Digital cameras have become popular over film cameras because of the following features:

·         LCD screen – allows users to view the photos and videos immediately

·         Storage – can store thousands of pictures

·         Picture development – allows users to choose and pick which pictures to develop

·         Size – takes up less space and can be easily carried

• Scanner – is an input device that reads an image and converts it into a digital file. A scanner is connected to a computer through USB.  There are different types of scanners:

·         Flatbed scanner – uses a flat surface to scan documents

·         Sheetfed scanner – like a laser printer where paper is fed into the scanner

·         Handheld scanner – the scanner is dragged over the page to be scanned

·         Card scanner – for scanning business card

• Touchscreen – is an input device that allows users to interact with a computer using their fingers. It is used widely in laptop monitors, smartphones, tablets, cash registers and information kiosks.  Most common functions of touchscreens are as follows:

·         Tap

·         Double-tap

·         Touch and hold

·         Drag

·         Swipe

·         Pinch

• Barcode Reader – also known as barcode scanner or point of sale (POS) scanner, is an input device capable of reading barcodes.
• Webcam – is an input device connected to the computer and the internet that captures still picture or motion video.
• Biometric devices – is an input device used to input biometric data into a computer. Here are the types of biometric devices:

·         Face scanner

·         Hand scanner

·         Finger scanner

·         Voice scanner

• Stylus – is a pen-shaped input device used to write or draw on the screen of a graphic tablet or device. Initially it was just used for graphic tablets and PDAs, but now, it has become popular on mobile devices as a replacement for the user’s fingers.  It’s used for more accurate navigation and to keep oils from user’s fingers off the device screen.

Types of input devices

·         Audio conversion device

·         Barcode reader

·         Biometrics (e.g., fingerprint scanner).

·         Business card reader

·         Digital camera and digital camcorder.

·         EEG (electroencephalography)

·         Finger (with touch screen or Windows Touch).

·         Gamepad, joystick, paddle, steering wheel, and Microsoft Kinect.

·         Gesture recognition

·         Graphics tablet

·         Keyboard

·         Light gun

·         Light pen

·         Magnetic ink (like the ink found on checks).

·         Magnetic stripe reader

·         Medical imaging devices (e.g., X-ray, CAT scan, and ultrasound images).

·         Microphone (using voice speech recognition or biometric verification).

·         MIDI keyboard

·         MICR

·         Mouse, touchpad, or other pointing devices.

·         OMR (optical mark reader)

·         Paddle

·         Pen or stylus

·         Punch card reader

·         Remote

·         Scanner

·         Sensors (e.g., heat and orientation sensors).

·         Sonar imaging devices

·         Stylus (with touch screen).

·         Touch screen

·         Voice (using voice speech recognition or biometric verification).

·         Video capture device

·         VR helmet and gloves

·         Webcam

·         Yoke

What are the input devices of my computer?

Every computer comes with a keyboard and a mouse (touchpad with laptop), which are considered input devices. As far as other input devices, it depends on what was included with your computer and what's connected to the computer. The best method of determining all of the input devices your computer has is to go through the list above.

What does an input device send to a computer?

What an input device sends (inputs) to a computer depends on the device. Additionally, all input devices send data from the device over a cable or wireless transmission to the computer. For example, as you move a computer mouse, the data sent to the computer is the X-Y axis movements used to display the mouse cursor on the screen. You can see a live example of this on our x-axis definition.

Why does a computer need an input device?

Today, input devices are important because they are what allows you to interact with and add new information to a computer. For example, if a computer had no input devices, it could run by itself but there would be no way to change its settings, fix errors, or other various user interactions. Also, if you wanted to add new information to the computer (e.g., text, command, document, picture, etc.), you wouldn't be able to do so without an input device.

What is the difference between an input and output device?

An input device sends information to a computer system for processing, and an output device reproduces or displays the results of that processing. Input devices only allow for input of data to a computer and output devices only receive the output of data from another device.

Output devices

An output device can receive data from another device and generate output with that data, but it cannot send data to another device. Examples of output devices include the following.

·         Monitor - Receives data from a computer (output) and displays that information as text and images for users to view. It cannot accept data from a user and send that data to another device.

·         Projector - Receives data from a computer (output) and displays, or projects, that information as text and images onto a surface, like a wall or a screen. It cannot accept data from a user and send that data to another device.

·         Speakers - Receives sound data from a computer and plays the sounds for users to hear. It cannot accept sound generated by users and send that sound to another device.

Input/output devices

An input/output device can receive data from users, or another device (input), and send data to another device (output). Examples of input/output devices include the following.

·         CD-RW drive and DVD-RW drive - Receives data from a computer (input), to copy onto a writable CD or DVD. Also, the drive sends data contained on a CD or DVD (output) to a computer.

·         USB flash drive - Receives, or saves, data from a computer (input). Also, the drive sends data to a computer or another device (output).

Most devices are only input devices or output devices, as they can only accept data input from a user or output data generated by a computer. However, some devices can accept input and display output, and they are referred to as I/O devices (input/output devices).

For example, as you can see in the top half of the image, a keyboard sends electrical signals, which are received by the computer as input. Those signals are then interpreted by the computer and displayed, or output, on the monitor as text or images. In the lower half of the image, the computer sends, or outputs, data to a printer, which will print the data onto a piece of paper, also considered output.

Input devices

An input device can send data to another device, but it cannot receive data from another device. Examples of input devices include the following.

·         Keyboard and Mouse - Accepts input from a user and sends that data (input) to the computer. They cannot accept or reproduce information (output) from the computer.

·         Microphone - Receives sound generated by an input source, and sends that sound to a computer.

·         Webcam - Receives images generated by whatever it is pointed at (input) and sends those images to a computer.