When GDI+ came out, I remember all the brouhaha about how it was the \"new, faster, better\" way to display stuff in Windows. But everytime I looked at it, it seemed to me that
GDI+ is built over GDI, and adds several more features. For example, GDI+ adds support for transparency, anti-aliasing bitmap stretching, etc...
GDI+ is mainly a Object based API, and GDI is a function api. Most of the functionalities in GDI+ are not hardware optimized (there are handled by software), to contrast with GDI. For example, in GDI, BitBlt is handled directly by hardware. GDI+ bitmap painting functions are not.
GDI+ is a powerful API, but be careful with its performance.
GDI+ is available in C++, COM and .NET