Denso Wave in 1994. It is an improvement on the widely used bar code as it is easily read and contains information in both the vertical and horizontal directions and is really popular in Japan.
You can download the trial edition of QR Code/Bar code generation software on the Denso Wave site or you can generate your own QR code at Kaywa.com.
If you want to read QR codes, all you need is your mobile (with camera) and the Kaywa reader. Just download the reader, scan by taking a picture and you then get the info on your mobile. Haven't tried it myself but according to some reviews I read on the net, including here and here, it's quite good.