What is "directwrite"

DirectWrite is a text layout and glyph rendering API by Microsoft. It was designed to replace GDI/GDI+ and Uniscribe for screen-oriented rendering and was shipped with Windows 7 and Windows Server 2008 R2, as well as Windows Vista and Windows Server 2008 (with Platform Update installed). DirectWrite is hardware-accelerated (using the GPU) when running on top of Direct2D, but can really render on the CPU to any target, including a GDI bitmap.