 Input devices allow you to enter information into the computer and interact with it. Different input devices handle different types of information. In some cases, like a microphone, the information has to be digitized. Some commonly used devices are keyboards, mice or trackballs, touchscreens, and scanners. The KeyboardOne of the most common means of entering information into a microcomputer is through the keyboard. Styles may vary, but the basic components are standard for most keyboards. The picture above is of an ergonomic keyboard designed to be more comfortable to use than the usual one. Show
The standard keyboard has four groups of keys. The alphanumeric keys and the numeric keys enter text into the computer. The function keys are used by programs as keyboard shortcuts to commands. The cursor-movement keys allow you to move the cursor to various positions on the screen. The cursor is the point on the screen which is active, and where the information you enter will appear. The Mouse and TrackballA mouse or trackball allows you to move the pointer or cursor that is on the screen and to select items by clicking on them.The mouse rests on a mousepad or desk top, and when the mouse is moved around, the pointer on the screen imitates the motion of the mouse. When you move the mouse, a ball that protrudes underneath the mouse is rolled against sensors within the mouse. These sensors track the movement of the ball, sending messages to the computer about where to put the pointer. The trackball is like an inverted mouse. It remains stationary on the desktop and is sometimes clipped to the side of the computer. The pointer on the screen is moved by rolling the ball, with your thumb, in the direction you want the pointer to travel. Both the mouse and trackball have buttons which send a signal to the computer when clicked. Most PC devices have two buttons, the left button commonly performing a function, and the right button revealing the options available from the current position. Because of the free manner in which the mouse moves the pointer, it is a tool which enables freehand drawing and sketching, an activity not possible with cursor-movement keys. The TouchscreenTouchscreens are commonly seen in areas where the interaction humans have with the computer must be kept simple, and where dust and dirt would interfere with the computer's input. They are popular on factory floors and in public areas such as banks and museums.Touchscreens allow you to make a selection from various options displayed on the screen. Different types of sensors can detect which area of the screen has been touched as if the user had used a mouse. A touchscreen is both an input device, in that when you touch it information is passed to the computer, and an output device, in that you can read information on the screen. The ScannerScanning devices help input images into the computer by digitizing them. They are capable of scanning colour or black and white graphics and converting them into data that can be manipulated by the computer. Combined with OCR (Optical Character Recognition) software they can be used to "read" printed text and convert it not to an image of the page, but to a stream of characters that can be manipulated in a word processor.The image scanner uses lights and sensors to scan the image and detect the patterns of light reflecting off the surface. The images that are detected are converted into bitmaps. A bitmap is a grid of dots represented by bits. The bit pattern is stored in the computer's memory. One commonly seen image scanner is the bar-code reader, used in supermarkets and libraries. It reads UPCs, or Universal Product Codes. The UPC is comprised of a pattern of bars which contains inventory information. Flatbed scanners look similar to photocopiers, and can "read" pages of printed text or capture images. If capturing text, you have to use optical character recognition or OCR software. OCR software reads the bitmapped images sent from the scanner, and compares them to its knowledge of recognizable characters. It then translates the images into text code. Other Input DevicesOther input devices include:
Return to Top of Page Created by: Suzanne A. Acharya, 15 June 1995. Copyright: Geoffrey Rockwell, McMaster University. Last Updated: Oct. 1995 Which device is used to point and select items on computer screen?The computer mouse (also called pointing device) is an important tool used to communicate with your computer. This tool allows you to point to objects on the computer screen, click and select them, or move them.
Which of the input device that rolls on a desktop and controls the position of the cursor on then on the screen?A computer mouse is a handheld hardware input device that controls a cursor in a GUI (graphical user interface) for pointing, moving and selecting text, icons, files, and folders on your computer.
What is the input device used to move the pointer on screen?An input device used to move the pointer (cursor) on screen. The major pointing device is the mouse for the desktop computer and the touchpad for the laptop, although many road warriors bring along a mouse. Pointing sticks are available on some laptops, and a small number of users prefer trackballs over the mouse.
What type of input device that lets you select options from on screen menus?What is a touchscreen? A touchscreen is an electronic visual display that also incorporates an input device that responds to touch. This allows users to select options from a screen by simply touching them.
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Which among the input device you roll on your desk to point to and select items on your screen?
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