Input Devices Purpose and Examples

What is the Purpose of an Input Device?

The purpose of an input device is to enable computer operators to have control of the computer and send data such as text, images, or sounds to the computer. An input device such as a keyboard will feed text characters for word processing and enable the computer user to perform specific control functions. Input devices convert raw data into formats understandable by the computer for processing by the central processing unit (CPU) to produce an output. Therefore, the input device acts as a link in communicating with the processing unit.

Input devices are essential to the overall functionality of a computer because they allow users to add, edit, or feed a new set of data or instructions to the computer. Input devices enable users to interact with the computer by either inputting numerals, characters, or gaming instructions into the computer. For example, the computer can run by itself without an input device. Still, a user cannot be easily able to change instructions and settings, fix errors, correct inaccurate data, or carry out other user interactions without an input device. Since it is not possible to communicate to the computer processing system without an input device, it would not be easy to have a computer do what human users desire without the input device.

Types of Input Devices

Parts of the computer that receive input include a touchscreen, keyboard, and modem. The information that computer input device systems can record includes text, pointing, movements, audio, and video. Types of input devices include keyboards, pointing devices, and data entry devices.

• Keyboards- Are primary input devices used to key in information and other command functions in the form of text into the computer. Keyboard buttons enable users to execute specific commands to the computer. Some modern computers are manufactured with on-screen virtual keyboard software as a backup just in case the hardware fails. Typical keyboards use applying pressure on keying buttons as a modality of data input. The keyboard is a discrete input since it involves pressing buttons. Discrete input devices work in the concept that signals are either on or off. They include photocell sensors, open and close switches, and push buttons. Continuous input goes one further step than discrete input by letting users move their hands from one point to another to finish inputting information into the computer. For instance, typing a sentence on a keyboard requires that fingers move from one key to another until the desired work is put together. Additionally, keyboards have one degree of freedom; i.e., the keyboard keys can perform only one specific function at a time.
• Pointing devices- Are input devices that enable a user to move the computer's cursor when selecting, pointing, or manipulating any text or object. Pointing devices include a computer mouse, trackball, stylus, and touchpads. Pointing devices use movements as a modality of input. The movement of pointing devices across the computer screen is fast enough, which makes them discrete input devices. Pointing devices have several degrees of freedom. For example, the 3D navigator mouse designed for computer-aided design (CAD) applications has six degrees of freedom.
• Data entry devices- Refer to all input devices used to send data into the computer. These include optical character recognition (OCR) and scanners that use vision as a modality of input. Laser scanners, for instance, are both discrete and continuous and have two degrees of freedom.

Examples of Input Devices

There are several examples of input devices. These include:

• Mouse- A mouse is mainly used to point and move the cursor on the computer screen and click a corresponding position or object using clicking buttons. The mouse has right and left click buttons and a middle roller key button. Modern computer mice use laser technology to track and control the cursor's movement. Additionally, some modern computer mice are wireless.

A mouse is an example of a computer input device.

• Joystick- A gaming joystick is used for movement and controlling characters such as vehicles in virtual reality games. It also doubles as a pointing device, just like a mouse. Joysticks have multiple buttons for more specific game features.

A precision joystick is an example of a computer input device.

• Webcams- Are used to capture images and convert them to digital form. A webcam is used for video conferencing and can simultaneously record audio and video. Webcams cannot operate without being connected to the computer.
• Trackpads- These are primarily embedded on laptops to help navigate the screen. However, one can still connect an external mouse to a laptop. Trackpads have a surface that detects touch and movement of fingers to move the cursor correspondingly.
• Scanner- This input device enables the conversion of hardcopy images into a softcopy digital format. The technology reads characters and pictures and transfers them to the computer storage for further manipulation.

A photo scanner is a data entry device.

• Microphones- These are voice input devices that read sounds from the surroundings and convert them to electrical sound waves that the computer can store. Microphones can be used for sound presentations or voice calling.

Due to advancements in technology, touchscreen technology has become widely used as a computer interaction module. Touchscreen technologies differ from traditional input devices such as keyboards and mice in that they do not use buttons but instead operate on a touch of the screen to point to the desired element. Playing a mobile screen game by moving the whole device, however, is not a touchscreen technology.

Devices used to play computer-based games include keyboards, gamepads, and joysticks. A joystick or gamepad is not necessary while playing computer-based games. However, they make playing such games more fun, especially fast-action games.

Lesson Summary

Computers are electronic devices that can receive, process, store, and retrieve data. The components that aid in a computer's functionality can be broadly categorized into input devices and output devices. Input devices send information signals and commands to the computer, whereas output devices receive data signals from a computer. Types of input devices include keyboards, pointing devices, and data entry devices. Computer input devices record types of inputs, including text, audio, videos, etc. Input devices can be broadly categorized according to the input modality, whether discrete or continuous, and the number of degrees of freedom involved. Some examples of input devices include:

• Webcams- Are used for video conferencing and can simultaneously record video and audio.
• Trackpads- Are usually made intact with laptops to help navigate the screen.

An external mouse can still be connected to a laptop at the user's convenience. Touchscreen technology differs from traditional input systems such as the keyboard because they do not use buttons, but rather operate through the touch of elements on the screen. Devices used in computer-based games include joysticks and gamepads. A joystick or gamepad is unnecessary while playing computer-based games. However, they make games a little more fun, especially the fast-action games.