Hello Friends in this Post we will see Input Devices In Detail
Input devices are those devices by which we can input our data or instructions into the computer. Input devices facilitate communication between a computer and a human.Data can be text,graphics or sound etc. There are many types of input device used according to needs, some of the commonly used input device are discussed below:
Keyboard:
keyboard is the most commonly used input device attached with all the computers . It is just like a typewriter. A keyboard is composed of different types of push buttons also called keys used to input letters, numbers, and symbols into computer and perform additional functions.
Generally 104 OR 108 keys consists in the keyboard these can be categories as :
Function keys: F1 to F12. Each function key has unique meaning and is used for specific purpose.
Control keys :Ctrl, Shift, Alt ,Home,End,Insert,Delete,Escape(Esc),Page Up,Page Down.
Alphabetic keys : A-Z(upper case), a-z(lower case)
Arrow keys or Cursor keys: ↑ → ← ↓ , for moving the cursor in respective directions.
Numeric Keypad: Numbers and mathematical signs in right hand side for numeric date use.
Symbolic keys : ; , " ? @ ~ ? : , for symbolic used.
Special Purpose Keys: Enter,Shift,Caps Lock, Num Lock,Print Screen,Space bar,Tab.
Computer Mouse: Mouse is the most popular pointing device. Its design is just like mouse(चूहा) therefore it is called mouse.It is used to move the pointer on the screen at the desired position. It is a most commonly used cursor-control device ,It is small palm size box having a round shaped ball at its bottom, the movement of the mouse is sensed by the ball and sends the specific signals to the CPU when the mouse buttons are pressed which then performs the required functions .There are two depression switches on the top , sometimes these are called Left click and Right click. Mouse can be attached with the computer in two ways either with the help of wire or without wired some times called wireless connection. The Mouse is used to move the pointer at the exact position , it is not used to enter the text so it is used with the keyboard.
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| Wired Mouse |
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| Wireless Mouse |
Types of Mouse :
Wired Mouse: This type of mouse connects to the computers or laptops through a USB port and transfer data using the cord or wire.
Wireless Mouse: This types of mouse connects to the computer through the wireless system j.e signals. The receiver accepts the signals and decode them in order to find the type of button pressed and perform the required function. sometimes wireless mouse are also called Bluetooth mouse as it works as other Bluetooth devices.
Wired mouse work faster than wireless since it is connected directly through wire instead through signals as in the case of Bluetooth mouse. But depending on the place and needs either can be used.
Scanner : A scanner is an input device attached with the computer used to scan text, images, documents, or handwriting sheets or papers. Sometimes information either in the form of images or text that is available on paper is needed on a computer. The basic function of a scanner is to convert a document into a digital format.
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Scanner |
Types of Scanner
Scanner is an important part of computer.The task of Scanner in the computer is to scan the hard copy of the document and convert it into soft copy or digital format. There are many types of scanner according to their design and functionality , some of the most popular names out of these are listed below:
Flatbed Scanner : It is similar to a photocopier machine, in which the image is scanned by placing it on the flat surface of the scanner.
Drum Scanner : Drum scanners are used to scan a document and print at a very high resolution rate. It can give you a high range of resolution, detail, sharpness, dynamic range, and color rendering. Because of its high cost, only a few companies make these scanners.
Sheet-fed Scanner: It feeds the image through rollers. As the paper passes through the roller, the scanner reads the image and prints it on a flat sheet.
Hand Scanner : As the name implies , for scanning with this, it is taken by hand and taken over the image. BarCode Scanner is a good example of this.
OCR: Optical Character Recognition
OMR: Optical Mark Recognition
BCR: Bar Code Reader
MICR : Magnetic Ink Character Recognition
Trackball
A trackball is a pointing device similar to a mouse, but it has a ball at the top, which is rotated with the help of fingers to control the movement of the pointer. They are often used as an alternative to the mouse.
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Trackball |
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Trackball |
The trackball is very comfortable to use, as it doesn't have to be moved around like a mouse to control the pointer. Apart from this, it is not necessary to have a flat surface to use it. The difference between mouse and trackball is that you don't have to move the trackball like a mouse, but you just have to move your finger over its ball. Along with this, buttons are also given, which you can use as left and right click. They are now also used in laptops and notebooks. In laptops, it is given in the middle of the keyboard button, with the help of which you are able to point something on the screen of your laptop. This is a kind of mouse moving up and down. It is connected at one place with the help of a socket.
How does trackball work? :
The trackball performs its function by reading the optical sensor. With the help of optical sensor, it takes information from the trackball directed by you. Whenever you move it in any direction, some dots start moving in it, then the optical in the trackball recognizes this movement and moves the cursor and marks the pointer on the information given by you.
Microphone : Microphone is an important input device, by which sound is given as input into the computer. For example, when you use Voice Recorder, the laptop's microphone detects that sound and an electronic signal is transmitted to the laptop.
After which the analog-to-digital converter (ADC) converts that analog data into digital data so that that recording can be stored in the laptop. Microphones are used for many tasks such as - Voice call, Voice over, Video conferencing and Speech recognition etc.
Joy Stick:
Like the mouse, the function of the Joystick is to control the movement of the cursor on the computer screen. Its main use is to play computer video games like flight simulator etc. There is a stick in it, which will move the cursor in the direction you will move by reading it by hand.
Joystick is an another type input device. It works like a trackball. It has two balls and a stick. A stick is attached to the balls in such a way the ball can be easily rotated using a stick.Joystick is mostly used in playing video games, Computer Aided Design(CAD) and simulator training etc. Some buttons are also given for control in Joystick, which are called Triggers.
