What are they?:
QR Codes, short for Quick Read Codes, are digital representations (much like Bar Codes) of text, geo-locations, and URLs.
The difference between QR and Bar Codes, is that QR Codes can hold a LOT more information.
<---This is what they look like.
<---By the way, if you scan this one, you will go to my blog. But you are already here, so you don't need to. :)
Why are they important?
Most magazines, advertisers and even business cards feature QR Codes. These are the quickest way, currently, to show a lot of information in a short amount of time, and to show that the user is "with it" (as in active in the digital age).
How do I make one?
QR Codes are extremely easy to make, and there are many free websites that will convert your text, URL, images, or geo-location information. I used qrcode.kaywa.com. You should feel free to look around for a generator that you feel comfortable with.