While a barcode only holds information in the horizontal direction, a QR code does hold information in both horizontal and vertical directions. Due to this, a QR code holds hundreds of times more information than a barcode.
With that being said they have different purposes, and there about the same developed as each other, unless you count how much information they can store.
the numbers are the size of the letters you type. the ab with the line through it is for marking stuff off of like a list or something. and the one all the way on the right I can't see good enough to tell what it is.
