The Windows RT user interface is identical to Windows 8 and includes the same tile-based Start screen. It also provides access to the traditional Windows desktop, where you can manage files and folders and run applications. While you can use Windows RT with a standard keyboard and mouse, it is designed primarily for touchscreen input. The operating system features an "always on" design, which means it receives mail, contacts, and calendar updates even while in standby mode.
While Windows RT looks and feels like Windows 8, it cannot run all of the applications that Windows 8 runs. Instead, Windows RT can only run software programs downloaded from the Windows Store. If you attempt to install an unknown third party app in Windows RT, you will see an error message saying the app cannot run on the PC. In order to install a new program on Windows RT, you must first click the Store tile on the Start screen and download the program directly from the Windows Store.