1. The position detection patterns are located at the three corners (top right and left and bottom left). These ensure clear orientation.
2. An alignment pattern can be recognised in the lower right quarter. This serves as additional orientation, especially with larger codes. Depending on the amount of data, it may even be present several times.
3. The timing pattern consist of alternating dark and light modules. They always begin and end with a dark module and indicate the size of the data matrix.
4. Version information provides data on the version of the QR-Code displayed. The various versions differ in the number of modules and configurations.
5. The format information is important for error correction: it gives information about the level of error correction. Four different levels are standard:
As the smallest level: Level L = 7%.
Level M = up to 15% offers somewhat more protection.
At Level Q = up to 25%
And finally the highest, Level H = up to 30%.
The percentage indicates how badly the QR-Code may be damaged in order to still be readable. However, as the error correction level increases, the possible amount of stored data decreases at the same time.
6. Finally, the data area contains the encrypted information.
These were all 6 components in the structure of the QR-Code. Of course, there are also special forms where parts are missing or have been replaced by others. However, this describes the basic structure of a traditional QR-Code.
