The Start button, an iconic part of Microsoft’s operating system since it was introduced in Windows 95, is missing from the latest test version of the upcoming Windows 8.

The Start button evolved to become the operating system’s “launchpad”, offering access to software, files and search functions.

Earlier test versions of Windows 8 had flattened the recognizable “orb” – but the new build removes it altogether, according to leaked screenshots from tech site The Verge.

Microsoft has not announced a release date for the new operating system, built to work with touchscreens as well as on conventional PCs, but it’s widely expected to release in the second half of this year.

“Fear not though, the Start button functionality isn’t as dead as it seems,” reports The Verge.

The Start button, an iconic part of Microsoft's operating system, is missing from the latest test version of the upcoming Windows 8

Although the button itself might be absent, the functions are still there, just accessed via a “hot corner” designed to work equally well with touchscreens or computer mice.

“We have confirmed with sources close to Microsoft’s Windows 8 development that a hot corner has replaced the Start button orb,” says The Verge.

A thumbnail-like user interface will appear in Metro or desktop mode, providing a consistent way to access the Windows desktop and Start Screen in Windows 8 regardless of touch or mouse input.

Windows 8 is a radical reinvention of Microsoft’s operating system.

Windows 8 is built to operate on tablets as well as PCs, and looks more like the Windows Phone operating system – with a tile-based “start” screen akin to the menus of apps offered in smartphone operating systems.

Navigation is done by swiping a finger across a touchscreen – although you can also use a mouse or even the direction keys.

The system will also be built to rely heavily on “cloud” information storage, with a Windows Live login used to access some features, and heavy integration with online storage services such as Microsoft’s SkyDrive.