The original pool of internet addresses has officially run dry.

The last five blocks of the IP Version 4 addresses have been handed over to the regional bodies that distribute them. Those five blocks, called /8s and which contain 16 million addresses each, are expected to be completely depleted by September 2011. The move to the new addressing scheme, IP version 6, is under way but could take years to complete.

"This is one of the most important days in the internet's history," said Rod Beckstrom, head of net overseer Icann at a press conference called to mark the handing over of the final five blocks.

"It is a point that the founders of the internet thought would occur far in the future," he said. "It gives us an opportunity to shift to an internet protocol that offers a pool so large that it is difficult even to imagine."

IPv6 has a pool of addresses a billion, trillion times larger than the 4.3 billion that IPv4 can support. While that pool of 4.3 billion addresses was seen as plenty when the net was getting going, its recent growth has seen it get used up very quickly. The shift to IPv6 was needed, he said, to support the continuing growth of the net and its greater use by all kinds of connected devices.

"The future of the internet and the innovation it fosters lies with IPv6," said Mr Beckstrom.

A QR Code is a specific matrix barcode (or two-dimensional code), readable by dedicated QR Barcode reader and camera phones. The code consists of black modules arranged in a square pattern on a white background. The information encoded can be text, URL or other data.

Common in Japan, where it was created by Toyota subsidiary Denso-Wave in 1994, the QR code is one of the most popular types of two-dimensional barcodes. QR is the abbreviation for Quick Response, as the creator intended the code to allow its contents to be decoded at high speed.