Observation consists of receiving knowledge of the outside world through our senses, or recording information using scientific tools and instruments. Any data recorded during an experiment can be called an observation.bservation consists of receiving knowledge of the outside world through our senses, or recording information using scientific tools and instruments. Any data recorded during an experiment can be called an observation.
A barcode scanner is a device that is used to read the printed barcodes. A barcode consists of a series of parallel, adjacent bars and spaces that are decoded with the intensity of the light reflected by them. When the scanning is initialized, the scanner lens reads the entire code with the help of the light source and converts the code into 0s and 1s.
Thus decoding is done for the barcode and the result is sent to the output device. Types of barcode scanners: The barcode scanners can be classified into two main categories. They are &bullContact readers: These devices are normally held in the hands. To read a barcode this type of readers must either touch the code or come close to it. &bullNon-contact readers: These devices need not be close to the barcode to read the code. These scanners use either a moving beam or a stationary beam, but mostly they have a moving laser light beam.