Codes are used to transform data into a format, which is more convenient for the target application. One of the most common codes is the bar code, which can be optically scanned. Bar codes are found on nearly every packaging. Subsequently, supermarkets, for example, are able to rapidly capture the data on the bar codes at the check out counter.
Bar codes are used a lot, but the use of the ASCII code exceeds the use of bar codes by far, even if we are not aware of this fact. Every keystroke on a keyboard is transformed into a bit string the computer is able to interpret.
Here you have the opportunity to experiment with commonly used coding methods.
A visit to http://www.codecheck.info can also be recommended. There you have the opportunity to scan a bar code online with your webcam and view the decoded result.