Computer Input Devices | Types, Example

In a computer system, input devices are electromechanical or hardware devices that allow the user to input (or enter) data, information, and instructions into a computer.

A computer takes input data in two ways, either manually or directly. When a user enters data into the computer by hand using keyboard and mouse, it is called manual data entry.

In case of direct date entry, a user enters data directly by transferring information from a source document (such as cheque using MICR) using a barcode reader into computer.

A computer gets instructions and data through the input devices. Then, its hardware component converts the input information or data into a suitable binary form acceptable to the computer.

Keyboard and mouse are the most common input devices used by the computer. A keyboard allows us to enter textual information while the mouse allows us to select a point on the computer screen by moving a screen cursor.

Types of Input Devices of Computer

We can classify input devices of computer into two types. They are as:

  • Basic input devices
  • Special input devices

Basic Input Devices: These input devices are always required to operate the basic input operations of a computer. Some of the commonly used basic input devices are keyboard, mouse, and microphone.

Special input devices: The input devices, which are not required to operate the basic operations of a computer are called special input devices.

Some commonly example of special input devices are scanner, digital camera, touch screen, optical mark reader, optical character reader, bar code reader, light pen, trackball, joystick, digitizer, and MICR device. These devices are essential for special input operations on the computer.

Let’s discuss the various input devices of a computer system with name and image.


In a computer system, a keyboard is the most common data entry device, similar to a typewriter. It is the main input device used to type text information in the form of alphabets, numbers, and other characteristics into the computer.

Keyboard helps us to type text and commands to direct the computer to do certain actions. We enter data or text into the computer by simply pressing keys.

In 1800 century, the first keyboard was developed named QWERTY keyboard. It was originated from a typewriter keyboard.

A standard keyboard comprises keys for separate letters, numbers, and special characters, as well as keys for particular functions. The number of keys on a typical keyboard can have more than 100 keys, as shown in the below figure.

Computer input devices: Keyboard

(a) Numeric keys: The keys having numbers 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 are called numeric keys. These keys are used to type numbers into the computer.

(b) Alphabetic keys: The keys having letters A, B, C, D, etc. are called alphabetic keys. These keys are used to type letters of alphabets quickly.

(c) Mathematical keys: The keys having symbols like +, -, /, *, =, %, ?, <, >, ^, { }, [ ], ( ) are called mathematical keys in keyboard. We use these keys to input mathematical signs.

(d) Numeric keypad: A set of keys that contains the numbers from 0 to 9 is called numeric keypad. It is located on the right side of most keyboards, allowing us to enter numbers quickly.

(e) Function keys: A set of keys having F1 through F12 is called function keys. We can find it on the top row of the keyboard. These keys are used to give the special instructions depending upon the software used.

(f) Special keys: A set of keys used to perform several special functions is called special keys. These keys are Enter, Ctrl, Esc, Insert, Delete, Shift, Tab, Backspace, Alt, Caps lock, Spacebar, and Print screen.

Types of Keyboard

In the today’s market, there are different types of keyboards available. Each keyboard has its unique features, advantages, and disadvantages. Some of the popular keyboard available are:

(a) Standard keyboard: It is the most common type of keyboard that comes with mostly desktop computers. It has a set of 101 to 105 keys that includes letters, numbers, function keys, and other special keys.

(b) Laptop keyboard: It is a compact keyboard built into laptops. It has a smaller layout and fewer keys as compared to a standard keyboard.

(c) Gaming keyboard: This keyboard is specially designed for gaming enthusiasts. It has some additional features like customizable keys, backlighting, and macro keys that allow gamers to play games with more precision and speed.

(d) Virtual keyboard: This is a software-based keyboard that appears on the screen of a computer or mobile device. It allows users to type without a physical keyboard.


A mouse is a pointing device or hand held device used to move the cursor, draw sketches or diagrams, and select items visible on the computer screen. We can input data or information into the computer by pointing on it and controls the movement of a cursor on the display screen.

In 1965, Douglas Engelbart developed the first mouse at Stanford Research Institute. It had wheels on the bottom instead of a ball. Its name is derived from its shape, which looks like a mouse. Its wire connected with a computer can consider as mouse’s tail.

All Windows-based applications and GUI (graphics user interface) use mouse. A small input device mouse is connected to the computer system by a long wire that resembles a tail. Some newer mice are wireless available in the market.

Usually, a mouse contains two buttons: a primary button (usually the left button) and a secondary button and a wheel between the two buttons, which allows us to scroll pages smoothly over screens. We use the left button to select objects and text while we use the right button for accessing menus.

When we roll the mouse with our hand on a flat surface, the cursor on the computer screen also moves in the direction of the mouse’s movement. To select an item on the screen, we need to point to the item and then click (press and release) the primary button.

Thus, the mouse is the best pointing and selecting input device that allows us to move the cursor across the screen of computer in a smooth and speedy way.

Types of Mouse

We can classify a mouse into three types. They are:

  • Mechanical mouse
  • Opto-mechanical mouse
  • Optical mouse

1. A mechanical mouse is the most common and least expensive pointing device. It uses a rubber or metal ball at the bottom surface, which rotates as the mouse moves on a flat surface to move the cursor. It has a mechanical sensor that detects the direction of the rolling ball.

2. Opto mechanical mouse is also same as the mechanical mouse except that it uses the optical sensor to detect the movement of ball on the mouse pad.

3. On the other hand, an optical mouse is a pointing device that uses a light beam (usually light-emitting diode (LED)) instead of a rotating ball to detect movement.

As we move the mouse on a flat surface, the cursor on the screen also moves in the direction of the mouse’s movement. It is more accurate and often does not need a mouse pad to it.


A joystick is another computer input device that consists of a small, vertical lever mounted on a plastic base with a flexible rubber that is used to steer the screen cursor around. We can move a joystick in all the directions.

Joystick provides three types of control. They are:

  • Digital control
  • Glide control
  • Direct control

Digital control allows us to move the cursor in a limited number of directions, such as left, right, up, and down. Glide and direct control allow us to move the cursor in all directions (360 degrees).

We mainly use joystick in computer aided designing (CAD), playing computer games, flight simulator, training simulator, and for controlling industrial robots.


A trackball is another pointing input device similar to a mouse that controls the cursor movements and actions on a computer screen. It consists of a ball housed in a socket containing sensors to detect the rotation of the ball.

When we will rotate the ball by fingers in any direction, the cursor moves accordingly. The size of ball in the trackball varies from as large as a cue ball, to as small as a marble.

This pointing device is available in various shapes and forms, such as a ball, button, and square, but with the same functions. It is especially used in the notebook computer.

Touch Screen

A touch screen is a special kind of input device that allows the user to interact with a computer with the touch of a finger on the screen. We can directly select a menu item or the desired icon by touching with a finger. A touch screen is mainly used with smartphones, tablets, and computer screens.

Touch screen accepts the input when a finger or other object touches the screen. We normally use it when we need to access the information with minimal effort.

However, it is not perfect for large amount of input data. Touch screen is generally used in the information providing systems, such as hospitals, airlines, railway reservation counters, amusement park, etc.

Light Pen

A light pen is a hand held electro-optical pointing device that we use to draw lines or curves on the screen. We mostly used it for graphics work. It is a pen like device that is connected to the computer machine through a cable.

There is a light sensitive diode at the tip of the pen which sense the light coming from the screen. The light coming from the screen gives a signal to the photocell to respond by producing a pulse.

The processor receives this electric response and identifies the position to which the light pen is pointing. With the movement of a light pen over the screen, we draw lines or images.

Digital Camera

A digital camera stores the images digitally rather than recording them on a film. Once we take a picture with a digital camera, we can transfer it to the computer system and then we can manipulate an image with the help of image editing software.

The main advantage of using a digital camera is that making pics is inexpensive and fast because there is no film processing in the background.

List of Computer Input Devices with Name

A list of computer input devices with name is as follows:

  • Keyboard
  • Mouse
  • Joystick
  • Trackball
  • Digital camera
  • Touch screen
  • Light pen
  • Scanner
  • Digitizer
  • Microphone
  • Web camera
  • Optical character recognition (OCR)
  • Optical mark recognition (OMR)
  • Magnetic ink character reader (MICR)
  • Bar code reader
  • Smart card
  • Graphic tablets
  • Biometric sensor

In this tutorial, we have discussed all computer input devices in a brief with name and images. Hope that you will have understood the basic points of all the input devices of computer and enjoyed it in reading.
Thanks for reading!!!

Please share your love