Microsoft said the next version of its operating system used on most personal computers around the world will be called "Windows Vista." However, Microsoft stopped short of providing an exact launch date for the new version of Windows, expected to reach consumers sometime next year.

Microsoft, which developed the software under the codename "Longhorn," expects to make the test version available to developers and tech professionals by August 3, it said in a statement.

The new software is expected to sport a new graphical interface, giving it a new look and feel, and enhanced security and communications features.

"It introduces clear ways to organize and use information the way you want to use it," Microsoft said on its Web page for the new system.

"It seamlessly connects you to information, people, and devices that help you get the most out of life."

The operating system, used on around 90 percent of personal computers, accounts for around a third of Microsoft's revenue.