The device interface represents a virtual adapter; it is used to create resources. ID3D11Device1 adds new methods to those in ID3D11Device.
interface ID3D11Device1 : public ID3D11Device
Header: Declared in d3d11_x.h (d3d11_1.h on other Windows platforms).
Library: Use d3d11_x.lib (d3d11.lib on other Windows platforms).