Input output devices are responsible for sensing and reading data from the input medium and converting this data into the form that the computer can understand and process and this form of data is also referred as machine language also these devices are responsible for converting computer is too data into information that can be Red and understood by the user.
A computer can be proved useful only when it is able to communicate with its external environment through the input output devices they are also called as the peripheral devices because they constitute the periphery around the CPU a wide range of device is available and choice of a particular device is dependent on type of application.
Input Devices :
Input devices are used to enter the input i.e the data and the instructions into the computers main memory there is a wide range of input devices that can be employed according to the nature of application e.g keywords, pointing devices such as mouse and trackballs and scanners etc.
Keyboard :
It is an online device that is used for entering data directly into a computer data is entered into the computer by pressing keys available on it there are multimedia and internet ready keyboard the keyboard comes in different key nos.eg. 101,104,105,108,111,115 etc.
Mouse :
It is pointing device it let's you to move the cursor on the screen the mouse can be scroll or non scroll the mouse has left and right button the mouse can be wireless also they can have 3 to 6 buttons.
Barcode Reader :
It is an important device which is used to convert a barcode which is a pattern of printed bars on product into a code the computer can understand this pattern of bars is known UPC universal product code the bars have definite thickness and spaces between them.
Joystick :
It is a pedal it consists of a small vertical lever mounted on a base its handle can swivel 360° for giving direction inputs it is used to play video games on the computer.
OMR :
OMR stands for optical mark reader which find the presence of absence of the mark and the paper the race are thrown on the paper and their reflection determines the presence of the marks it is widely used in questionnaires.
OCR :
OCR stands for optical character reader which is used to not only detect the presence or absence of the mark but also the character on the document it is widely used to check the computer performa forms.
Touch Screen :
A computer display that enables the user to interact with the computer by touch areas on the screen.
MICR :
MICR stands for magnetic ink character reader which is widely used to check the banks check special magnetic ink is coated and read by device.
Optical Scanners :
Optical scanner scan scan typed document, pictures graphics or even handwriting into a computer.
Light Pen :
It is a pointing device used to specially for graphic works it detect light pulses, rather then emitting light as its name implies the pen consists of a photo cell placed in a small tube the user moves the tip of the pana over the screen surface, draw or write the desired text or image.
Voice Input Device :
Microphone is a boys input device it is most often used in multimedia voice recognizers accept the spoken word through a microphone and convert it into binary code that.