You can create your own QR code and direct people to a specific website, document, or any other type of media.

Rather than have a guest select your Wi-Fi network and then enter a fiddly password, just make them a QR code their iPhone can read. Here's how to do it. You wouldn't want to put a QR code for ...

These days, it's a snap to embed your contact information -- and in fact anything else you want to communicate -- in a QR code that you can insert in your PowerPoint slides.