Overview of GDI+
GDI+ is the subsystem of the Microsoft® Windows® XP operating system that is responsible for displaying information on screens and printers. As its name suggests, GDI+ is the successor to GDI, the graphics device interface included with earlier versions of Windows. GDI+ is an application programming interface (API) that is exposed through a set of classes deployed as managed code. This set of classes is called the managed class interface to GDI+.
A graphics device interface, such as GDI+, allows application programmers to display information on a screen or printer without having to be concerned about the details of a particular display device. The application programmer makes calls to methods provided by GDI+ classes and those methods in turn make the appropriate calls to specific device drivers. GDI+ insulates the application from the graphics hardware, and it is this insulation that allows developers to create device-independent applications.