Version 6.0 pioneered the concept of complete structural integration of graphics—with graphics interleaving seamlessly into all input and output, and allowing immediate manipulation using all of Mathematica's powerful language and dynamic capabilities. Version 6.0 also greatly extended the core graphics language—with opacity, smooth shading, new primitives and richer graphics data structures.
Graphics (modified) — now fully integrated into all input and output, and editable
Graphics3D (modified) — now with full real-time rotation, smooth shading, etc.
Graphics ► — interactive drawing tools and interactive graphics inspector
Arrow — general arrow primitive, with multiple heads, curved shafts, etc.
Polygon (modified) — now supports smooth shading and color gradients
Inset — arbitrary object inset into graphics
GraphicsComplex — polygonal mesh or general 2D or 3D graphics complex
GraphicsGroup — graphics selectable as a group
Opacity — transparency in 2D and 3D