QR Code, Quick Response Code

The QR code is a modern square 2D code. The marks in three of the four corners of the matrix provide the orientation. The code is well known by the mobile tagging for cell phones.

Which of the numerous types should I use to create a QR Code?
If you have no special wishes, simply choose the type QR Code. It creates a the smallest QR Code that is possible.

If you want to work with a fixed error correction, please select one of the following 4 types:

• QR Code ECC LEVEL L : 7% of the data can be restored.
• QR Code ECC LEVEL M : 15% of the data can be restored.
• QR Code ECC LEVEL Q : 25% of the data can be restored.
• QR Code ECC LEVEL H : 30% of the data can be restored.

These 4 types use fixed error correction and create the smallest possible code depending on the data to encode.

Alternatively, you can specify the symbol size. Select one of the types with fixed-size for this purpose, e.g. QR Code 45×45. The error correction is selected automatically depending on the amount of data as good as possible.

More information about this can be found at Wikipedia:
http://en.wikipedia.org/wiki/QR_code