Barcode
A barcode is a set of lines of different widths and sizes representing data, that when read help identify the scanned object. Barcodes are often used to help organize and index information or prices about an object. Barcodes used by the U.S. postal service that helps speed the delivery of mail is another perfect example of how a barcode could be used. The picture is an example of what a barcode of an address.
A BCR (barcode reader)or scanner, also known as a POS (point of sale) scanner is a hardware input device capable of reading a barcode using a laser. It can also print out the details of the product or log information about that product into a database. A perfect example of a barcode reader is a supermarket barcode scanner that reads and logs the price of a product. In the picture is an example of a barcode reader from HP.
Today, many smartphones with the proper apps are also capable of scanning and reading barcodes.
Like all other input devices, a barcode reader is bringing in (inputting) information from the outside world into a computer or other electronic device, which makes it an input device. If the barcode reader also has a screen that displays (outputs) results or prints results, it would be considered an input/output device.
A barcode printer is a hardware device capable of printing adhesive barcodes that can be attached to a product to identify it and help keep inventory.
Laser
Short for light amplification by stimulated emission of radiation, a laser is an intense beam of light first developed by Physicist Theodore Maiman on May 16, 1960. The picture is an example of a blue laser looks inside a Blu-ray disc player. Today, there are dozens of different uses of lasers, below are a few examples of where lasers are used in computers.
· Barcode readers.
· CD-ROM, DVD, Blu-ray, and other disc drives.
· CD and DVD writers.
· Laser mouse.
· Laser printer.
The word "laser" has become so common that most people are unaware that it's an acronym and it is no longer written in all uppercase.