While reading threads on this I have learned that someone wants to add QR code on his logo. But I don't know what the QR code is for? Why we need QR codes for logo or images?
QR code is a barcode "Quick response code" which is a 2d (square) code - it can be used for numbers/links/any text. Check out http://en.wikipedia.org/wiki/QR_code for more information. And the reason for wanting this in their logo, could be for many reasons, Usually however, to have phone numbers available, You can use a barcode scanner on your smart phone, Point it at the code and retrieve their phone number/email address/mobile website/any other useful information within seconds.
This is how Qr-codes look. Download any special application (QR-Code reader) at your phone and you'll be able to access some services quickly.
A QR code (abbreviated from Quick Response code) is a type of matrix barcode (or two-dimensional code) first designed for the automotive industry. More recently, the system has become popular outside of the industry due to its fast readability and comparatively[clarification needed] large storage capacity. The code consists of black modules arranged in a square pattern on a white background.The information encoded can be made up of four standardized kinds("modes")of data (numeric, alphanum- eric, byte/binary, Kanji), or by supported extensions virtually any kind of data.
A QR Code is a two-dimensional barcode, which has encoded in it a URL (web address), text, or other information. It can be read by a QR code scanner, including QR scanner smartphone apps.