Keyboard Keyboard, as the name suggests it is a board full of keys which can be used to give orders in different forms to a computer. There are approximately 100-110 keys on a keyboard. The keyboard can be broadly categorized as Alphanumeric KeysNumeric KeysFunction KeysHow Keyboard Works?Keyboard has a square matrix underneath the hood. There is a circuit beneath every key which is closed at normal time. When a key is pressed the circuit is closed and very small amount of current is passed through the keyboard. When the circuit is not open the key which is pressed is recognized by the mapping in character map which is stored in the ROM of the keyboard. Now that information from the ROM is passed to CPU using the PS/’2 Port for keyboard in CPU which is purple in colour.On Screen Keyboard Windows provide an On screen keyboard which could be operated with a mouse. It is very useful when we don’t have a working keyboard. It comes with many features like hovering through keys, scanning through keys, text prediction, transparency etc. Text prediction is helpful to type even more faster through on screen keyboard. Hovering through keys We can select any keys by changing the mode to “hover the keys” from the options menu and adjust the slider to the speed we want. When we take a cursor to the key which we want to press we just have to put the mouse pointer there and wait for a second for the key to be typed automatically.Scanning through keys If we don’t have a keyboard we can operate a keyboard using different devices such as a Joystick. It scans throughout the keyboard and we have to press a button on the joystick if we want to stop at that part of keyboard.How to access On Screen KeyboardGo to Start Menu — All Programs — Accessories — Ease of Access — On Screen Keyboard 2.) Press Windows key + R and type cmd — In cmd type “osk”.Touch Screen KeyboardTouch Screen keyboards are now available in Touch enabled devices like Tablet PC and laptops. Touch Screen Keyboards are also available in Touch Screen phones.