Windows 10 is an upcoming version of the Microsoft Windows operating system initially thought to be called Windows 9. Windows 10 unveiled on September 30, 2014, it is scheduled to be released in late 2015.

First hinted at in April 2014 at the Build Conference, Windows 10 aims to address shortcomings in the user interface introduced by Windows 8 by improving the user experience for non-touchscreen devices (such as desktop computers and laptops), including a revival of the Start menu seen in Windows 7, a virtual desktop system, and the ability to run Windows Store apps within windows on the desktop as well as in full-screen mode. Windows 10 will be available for desktops and laptops, and it has been announced it will be used on tablets, smartphones and other embedded Windows products.

Windows 10’s user interface is designed to tailor itself to the type
of device and available inputs, providing “the right experience on the
right device at the right time.” For non-touch devices, a variation of
the previous Start menu
is used as part of the desktop interface, featuring a traditional
application list and search box on the left side, with Start screen live
tiles on the right. A new virtual desktop system known as Task View was also added. Like OS X‘s Mission Control
function, clicking the Task View button on the taskbar (or alternately
swiping from the left side of the screen) displays all open windows and
allows users to switch between them, or switch between multiple
workspaces. Windows Store apps,
which previously could only be used full-screen, can now be used in
desktop windows. An “App Commands” menu on the app’s titlebar is used to
activate functions previously seen on the charms, or to switch between windowed and full-screen modes.[1][28]
Windows 10 also includes changes to the ‘Snap’ feature: if an app is
dragged to the corner of the screen, it will only fill a quarter of the
screen. When an app is snapped to one side of the screen, a new feature
called Snap Assist prompts the user to choose a second app, which
automatically fills the unused side of the screen.

The Start screen is still used in touch environments. Current Windows
10 builds use the same Start screen layout as Windows 8.1, but
Microsoft has demonstrated a newer Start screen design that includes a
column at its left to display shortcuts and the “All apps” button,
similarly to the Start menu. Another feature planned for future builds of Windows 10 is Continuum,
which handles transitions between touch-based and non-touch interfaces
on devices such as convertible laptops and tablets with keyboard docks:
When a keyboard is connected, users are asked if they want to switch
between a touch-optimized user interface and one optimized for mouse and
keyboard.