You can create several kinds of barcodes with One of the most common usage, is for generating 2-dimensional QR codes, that can be used i.e. for storing a URL.

1. Add to your webpage(s) the following link:
  <img src="">

2. generates on the fly a QR code that includes the address to your webpage. It uses the HTTP referer (yes, it's misspelled) to identify the address.

3. Alternatively, you can explicitly specify the message to be encoded in the code, using the parameter msg, i.e.

4. In addition to URLs, you can encode any information you want in your QR code, such as contact information, email addresses, youtube links, and much more! Look here for more examples!

Looking different types of barcodes? Look here for the list of supported formats!