Pointing devices types, functions, and advantages

A computer-pointing device is an input device that is used to move the cursor or pointer on the screen. They are mostly used to click, select, drag, point, and other user movements on the computer screen.

The main types of pointing devices are a mouse, trackpad, trackball, touchscreen, lightpen, stylus pen, and pointing stick. They are used mostly in GUI systems for moving the cursor on the screen. Their main advantage is they are user-friendly, versatile, and can be used for dimensional movements.

Functions of pointing devices

The devices can be used for a variety of purposes by users operating the computer. Some of the functions include.

1. Click: this is pressing the button on the pointing device to initiate a command. The click can be single, double, or triple click. It can also be left or right click.
2. Select: this is to highlight the content or an area on the screen. It is done by holding down the mouse button and moving the cursor over the content to be highlighted.
3. Drag: this goes hand in hand with drop. This is where you hold an item or icon on the screen and you want to move it to another location. You click hold and move the mouse button then release it in the right location.
4. Move cursor: cursor is a movable point that is used to show where the pointing device is currently located and where the command given will take place. A pointing device is used to move that insertion point.
5. Point: this generally means using the pointer on the screen to show or point to an object.
6. Scroll: This is moving the content of a document either vertically or horizontally.

Types and examples of computer pointing devices

There are many varieties of pointing input devices that are used with different types of devices for various functions. The most common types of pointing input devices are:

1. Computer mouse: this is the most common pointing device that is used on personal computers, servers, and all other types of computers. It is made up of 2 buttons (right and left) for clicking and a wheel in between for scrolling horizontally or vertically. We have a detailed article on the parts and functions of a computer mouse here.
2. Touchpad/trackpad: This is the most common on portable devices like laptops and it is used as a substitute for the mouse. It is a touch-sensitive component to is used to move the cursor on the screen. It is usually accompanied by 2 buttons on the side for clicking, although you can click by tapping on the pad.
3. Trackball: it is an input device that looks like an upside-down mouse. It has a ball on the top that is moved with a finger to move the position of the cursor on the screen. It is more ergonomically fit than a mouse to reduce repetitive strain injuries.
4. Touchscreen: this is becoming a common input component to most devices. The screen is sensitive to touch and it works both as a display and input device.
5. Light pen: this is a pen that is used to draw or make other gestures on a touch-sensitive screen. They are old technology and they were mostly used on the CRT monitor screens.
6. Stylus pen: they replaced the light pen and they are used in most modern touch-sensitive screens. You can read more on the types, functions, and advantages of the stylus pen
7. Pointing stick/Trackpoint: it is a small size pointing device that is positioned on some laptops within keyboard keys. The pointing stick is the size of a pencil eraser. It is placed between G, H, and B keys on the keyboard. It is positioned within the keyboard so that the user’s finger doesn’t need to move to the touchpad to move the cursor.

Advantages of pointing devices

1. Simple to use. Most of the pointing devices are simple to learn and use. User can self-learn how the device work.
2. Versatile. The devices can be used in a variety of activities and on different devices. They can be used in laptops, desktops, palmtops, etc for clicking, selecting, and dragging among other many functions.
3. Speed of operation. Users can increase the speed of operation when they combine the use of pointing devices and a keyboard. This is particularly when dealing with complex interfaces.
4. Multidimensional movement. These input devices allow the user to move the cursor in all directions on the screen. 
5. Allow the use of gesture input. Some devices such as touchscreen allow the use of gesture actions such as swiping, pinching, and zooming among others.

Disadvantages of pointing devices in the computer

1. Ergonomic issues. If the mouse and others are not used in the right way they can lead to repetitive strain injuries.
2. Users with some physical disabilities may not be able to use pointing devices.
3. Some devices like mice and trackballs require a flat surface to move on. 
4. Most commonly used in GUI systems. Pointing devices are not common devices when dealing with command line interfaces (CLI) but only in GUI systems.
5. Requires more system resources. Devices that use the pointing device require more processing power and memory for effective and fast system response.
6. The sensitivity of the device to touch can affect the user experience with the device. Devices like touchpads and touchscreens should be calibrated correctly to ensure the sensitivity is optimum.