Microsoft is launching Windows 10 as the new face of both Windows and eventually Windows Phone. At one point during Microsoft’s Tuesday press event.during Microsoft’s Tuesday press event, Terry Myerson, the executive vice president in charge of Microsoft’s OS group Microsoft is looking for user feedback, and what I demo'd on Tuesday may not be the same OS that customers receive next year.Windows 10 tentatively scheduled to be launched around the middle of 2015

Windows 10: Expanded Start Menu

it looks like someone conjoined the Windows 7 and Windows 8 experience.As you can see in the below screen on the left, there’s a list of frequently used apps, along with shortcuts to PC settings, as well as your documents and pictures folders. At the bottom, there’s a shortcut to launch an “all apps” view. It appears that you should think of Live Tiles more like notifications rather than app shortcuts, although you can use them either way.

If you want, you can resize the Start menu, increasing or decreasing its size and adjusting its position.

Windows 10: Multiple desktops

Instead of too many apps and files overlapping on a single desktop, it's easy to create and switch between distinct desktops for different purposes and projects ( whether for worker or personal use)

Windows 10: Search improved

In this latest version they moved the one of the major functionality of the Windows 8 Start page to the desktop environment of Windows 10. I am talking about the Search button it is added to the taskbar with this your "searching" for recent apps or documents is often quicker.

Windows 10: Snap enhancements

Working in multiple apps at once is made easier and more intuitive with snap .A new quadrant layout in Windows 10 allows up to four apps to be snapped on the same screen.it will even make smart suggestions on filling available screen space with other open apps.

For example that once you snap an app, Windows 10 suggests another, similar app that you might want to snap next to it, from a small collection of windows. The feature is intended to save you the hassle of hunting about through menus to actually construct a virtual desktop. Time will tell whether these suggestions will prove useful, but it’s a good start.

Windows 10: New Task view button

The new Task view button on the task bar enables one viewforall open apps and files, allowing for quickswitching and one touch access to any desktop created.