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Barcode Reader
A bar code is a set of parallel lines that appear on the products as their identification. You will
find most of the packages having these barcodes that can be easily read by barcode readers.
Bar code readers work by placing a beam of light on the lines that make up the bar code and
detecting the amount of light that is reflected back. The barcode read is then stored in the Barcode Reader
computer for preparing invoices.
MICR
The bank account number and other details are printed onto bank cheques which are read
by Magnetic Ink Character Recognition using a special magnetic ink. They are useful to
find out whether the cheque is genuine or fake.
MICR
Web Camera
A web camera or webcam is a type of video camera that saves images or visuals in realtime into a
computer via USB, Ethernet or Wi-Fi.
Web camera is used to create video links and helps us to set up authentic video conference stations.
Some built-in webcams can be remotely activated from far-off locations. Webcams can also be used
for security & surveillance purposes by monitoring the captured visuals. Web Camera
Processing Device—Central Processing Unit (CPU)
After taking the input from the input devices, the information is sent for processing. The computer uses its brain
to process the information. The computer’s brain is called the CPU or Central Processing Unit. CPU is basically
divided into three parts:
• ALU stands for Arithmetic Logic Unit. It is responsible for all arithmetical and logical
calculations.
• CU stands for Control Unit. It controls the flow of information in the system. The control unit
is responsible for the flow of data from input devices to the processing unit and then to the
CPU Chip output devices. It works like a traffic policeman who controls the traffic on the road.
• MU stands for Memory Unit. It is a storage unit that holds the processed or unprocessed data.
Output Devices
An output device is a physical component that converts the processed data or information into a human readable format.
Some of the commonly used output devices are:
Monitor (Visual Display Unit)
Monitor is a standard output device that is similar to a television screen. It is also known as
Visual Display Unit (VDU) or console. An input from any input device such as a keyboard can
be seen on the screen simultaneously. There are different types of monitors available in the
market depending on the size and color.
Monitor
These days the most widely used monitors in computers, tablets, smartphones, Smart TV, etc. are LCD (Liquid Crystal
Display). Its screen is made up of smaller elements called pixels. Resolution of any display unit is the number of
horizontal and vertical pixels. A higher resolution provides a smoother, sharper, and clearer image.
ICT Skills-I 49

