Microsoft demonstrated its forthcoming WinFS file system at the Professional Developer Conference in Los Angeles, claiming that the technology will offer easier access to data.

Instead of looking for files, WinFS identifies relationships between items such as images, documents, email messages and calendar appointments, allowing the user to search for objects dispersed over several applications.

The technology could, for instance, enable a query for all email messages to and from a client whom the user is meeting today.

"I can go into one application and build a list of people and go into another application and show their messages," Shishir Mehrotra, who is responsible for WinFS product planning, said during a session at the Microsoft developer event.

Mehrotra demonstrated an application where an estate agent could see a map of the homes for sale within a certain price range that were close to a property about which a client had inquired.

WinFS is Microsoft's next-generation file system. The company first spoke about the technology in 2003, and it was originally scheduled to be released as part of Windows Vista but has since been pulled from the operating system.

The delay has allowed the vendor to include items inside applications instead of just files, explained Mehrotra.

WinFS is now scheduled to be delivered through an update at a later stage. Microsoft released a first beta of the system last month.

The beta works with Windows XP only. While WinFS is designed to be part of Vista, Microsoft could decide to make it available for XP. The company will make that decision at a later stage, according to Mehrotra.

WinFS offers different 'schemas' for each group of items, such as messages, appointments and pictures, each of which has a number of predefined attributes.

The system will be able to determine the sender and recipient of email messages, for example, or the date and attendees for an appointment.

Although WinFS will come with a number of predefined schemas, software developers will be able to add more. This could turn out to become a weak spot for the technology, as it could lead to a plethora of overlapping or identical schemas, Mehrotra admitted.

"The best answer we have is that Microsoft will create [schemas] based on best practices," she said. "But there is nothing to stop you from creating additional schemas that do the same thing as an existing schema."