Notes on Input Unit

Input unit in a computer comprises devices responsible for providing data and controlling signals to an information processing system, such as a computer or information appliance. Examples of input devices include keyboards, mouse, scanners, cameras, joysticks, and microphones. The data entered does not require any conversion and fed directly into a computer. The input in a system is received by the Central Processing Unit (CPU) of a computer. Further, the input is processed to produce output in a system.

Keyboard

• The layout of a keyboard resembles a lot of that of a typewriter. The command is given to the device through the keyboard by various keys for entering letters, numbers, and characters.
• The keyboard has three types: DVORAK, QWERTY, and AZERTY.
• The size of the keyboard can vary depending on the user’s utility. Commonly available keyboards come with 84 keys or 101-102 keys. 
• It is connected to a computer system with the help of a USB or a Bluetooth device. A keyboard can also substitute the use of the mouse. 
• The keyboard’s arrow keys can do the same purpose as the mouse.

The different keys of the keyboard are 

• Numeric Keys: There are a total of almost 17 numeric keys. Their purpose is to enter numeric data and move the cursor. 
• Keyboard Shortcuts: These keys include the letter keys (A-Z) and the number keys (09).
• Control Keys: These keys are responsible for controlling the screen and pointer. It comes with four directional arrow keys. Some control keys are Home, End, Insert, etc. 
• Special Keys: Some common special keys are Enter, Shift, Caps Lock, etc.
• Function Keys: F1-F12 are the 12 keys function keys situation at the first row from the top of the keyboard.

Mouse

The mouse is a pointing device invented by Douglas C. Engelbart. The command is given to the device as the mouse enables the user to select and move the applications in a system by moving the cursor. 

Some functions of the mouse are:-

Move the mouse cursor, Open or run a program, Select, Drag-and-drop Hover, Scroll, and many other functions varying on the mouse type as some also have additional buttons.

Joystick

• C.B.Mirick invented it. A joystick is an input pointing device consisting of a stick standing on a base that can rotate. The command is given to the device by a joystick when the user rotates the stick of the joystick in preferred directions enabling the user to control the system by moving the cursor. 
• They are more precise and long-lasting than a mouse, so they are still utilised. It is used to move around the cursor’s position across a display screen, 
• It’s commonly used for gaming and allows users to move the characters and symbols easily.
• It sometimes consists of one or more push buttons that are controlled by the computer as well.

Light Pen

 It is a light-sensitive wand used with a computer’s CRT display. This device has an appearance of a pen used to draw on the monitor screen or select an item from the menu. The command is given to the device when the user points to displayed objects or draws on the screen, similar to a touchscreen but with greater positional accuracy.

Scanner

A scanner is an input device that works similarly to a photocopier. It’s used to convert data on paper into digital images to the computer’s hard disc, flash drive, or shared network folders for further processing. The graphics can get edited before they are printed. A scanner can even scan 3D objects such as cloth, shells, and somewhat flat coins.

OCR

A computer reading technique that can read the data entered in numbers, characters, and symbols is called an OCR. OCR stands for “Optical Character Recognition.” It is a technique to recognise text in documents that have been scanned into digital form. 

Barcode Reader

A bar code reader is a device that reads the data entered in a bar code. It works by flashing light beams on the barcode and extracting data from the code. Bar-coded data is often utilised to label things, number books, etc. 

Conclusion 

We currently live in a high-tech world where technology evolves constantly and rapidly. Keyboard, since innovated, has remained an undisputed monarch of the input devices. However, in the last few years, innovations like gesture recognition, speech recognition, projection keyboards, etc., have started to take over the tech geeks and other people due to their effortless utility. Gesture technology interprets and reads users’ commands given to the device by their hand movements with the motion sensors. Speech recognition has an inbuilt program to identify words and translate them into text. However, these technologies are yet to be made at pocket-friendly prices. Therefore, many users still prefer using keyboards.