New openating system to arrive 26 October

Apple is planning to release its next OS X version 10.5 on 26 October.

Code named Leopard, the latest installment of OS X is the first new version of the operating system since the April 2005 release of OS X Tiger.

Both the server and client versions of Leopard will go on sale at 6pm local time at retail and online stores. The company is currently accepting pre-orders through the online Apple Store.

One of the software's key features is Time Machine, an archiving and backup feature that allows users to restore files or file verions to a previous state. The feature can undo changes to a file, restore a system to a working state after a crash or restore files that were accidentally deleted. The software is based on the ZFS file system that was released under an open source license by Sun Microsystems.

Leopard will also have a new interface feature known as Stacks. It is intended to free up space on the desktop by organizing organizes files on the dock under a single icon, which can then be scrolled through vertically.

Leopard had originally been scheduled for release in June of this year at Apple's annual Worldwide Developers' Conference. The product was delayed by four months however when Apple had to move engineers to the development of the iPhone

In announcing the new version of the software, Apple chief executive Steve Jobs took his trademark romantic view on his products, calling it the "best upgrade we've ever released."

Leopard markets a single version of Leopard that is priced at $129. A server version of the software will cost $499 for a 10-client licence and $999 for unlimited clients.

Users who purchased a new Mac after 1 October will be eligible to receive a free copy of Leopard, though they will need to pay a $9.95 shipping fee.