What is a barcode ?

A barcode is a number, a word or a sentence expressed in a foreign language.

Why do we not write this word or number in English ? Because, when it is printed and you want to recapture it on the keyboard, you could make a mistake on reading or typing and also because this recapture takes time.

The barcode language, or rather the languages because there are several barcode languages, have been invented to enable an automatic reader to capture and transfer printed information to a computer, with minimal risk of error, near instantaneousness and decreased tiredness, regardless of the degradations due to aging, deformations, dirt and other incidents that a printed paper may encounter in work environments.

Why are there multiple barcode languages?

The human genius proceeded in stages, and at each stage corresponded a new language, more robust, more compact, more efficient. Several thousand barcode languages ​​have been invented, only a few have remained, either because they have advantages under certain circumstances, or because they have enjoyed success and investments such that they have remained in use.

What is a symbology, a coding, a standard ?

This is what we call above a barcode language, with three shades possible :