Table of Contents
What is Input
"Any data or instruction that is used by a computer is called input". This data or instruction can come directly from end user or from other devices. For example, while you prepare word documents or spread sheets, you use the keyboard to enter text & numbers and use command keys to save / print documents. You can also perform operations on computer using voice commands. These are all different methods of providing an input to a computer.
What is Input Device
"Input device translates words, sounds images, and actions that people understand into symbols that the system unit can process".
Input devices include keyboards, Mouse, digital Camera and light pen.
"An input device is a hardware device that is used to provide input (data / instructions) to a computer so that it can be processed".
Besides the widely used input devices like keyboard & Mice there are other different input devices that perform various input operations like a scanner scan images / documents. Webcams capture videos & images.
A keyboard is an essential input device that combines a typewriter keyboard with a numeric keypad. The special purpose keys and the function keys are used to perform a special taks like pressing Control key (CTRL) key in combination with “P” prints a document, or pressing the “F2” function key opens a window with help content about any issue or topic. Nowadays Multimedia keyboards are common as they have task specific keys & buttons. For example, volume control ext. Wireless keyboards are also popular these days, that can be connected to a tablet or a computer via Bluetooth.
The mouse is another essential input device that controls the pointer displayed on the monitor. A mouse can have 2 or more buttons. Mostly the Right-Mouse Button and the Left-Mouse button, and a wheel button for scrolling pages.
A mechanical mouse is considred as the traditional mouse and is now replaced by optical mouse. A mechanical mouse has a ball on the bottom, which is attached to the system unit through a cord. A mechanical mouse requires periodic cleaning.
Optical Mouse is widely used these days. Like the mechanical mouse, it does not have any moving parts. It emits & senses light to detect mouse movements. Optical mouse can be used on any surface with great precision as compared to Mechanical mouse.
A wireless mouse or cordless mouse uses infrared or radio wares to communicate with the system units. A wireless mouse is battery powered and can be connected to a laptop or tablet computer.
A very popular input device that is used for computer games. Different buttons are used for controlling the game. They can be used with gaming consoles like Xbox 360 or Playstation.
A touch screen is a particular kind of monitor screen covered with a plastic layer. Behind this layer are crisscrossed invisible beams of infrared light. This arrangement enables someone to perform actions by touching the screen with a finger or stylus. With it growing popularity touchscreens are used in smartphones, Automated Teller Machine (ATM) etc.
A scanner reads data or information from a source. This source can be a written document, on an image. A scanner, also called optical scanner can copy or reproduce text as well as images.
Bar Code Reader
You must be familiar with a Bar Code Reader from grocery stores & shopping malls. A barcode reader is a photoelectric scanner that reads the bar codes of a product. The bar code reader reads the bar code of a product and displays the information about the product, for example the price of the product.