Viewport 2.0 is the viewport and hardware renderer in Maya - it's the way you view your scene.
Viewport 2.0 provides a number of performance and display quality advantages and features that were not available in the legacy viewport. If you are transitioning to Viewport 2.0, see About Viewport 2.0 for more information about these benefits.
For tips on how to optimize performance for Viewport 2.0, see Optimize Viewport 2.0.
For solutions to common Viewport 2.0 issues, see Troubleshoot Viewport 2.0.
Use the Maya API to create plug-ins to draw, shade and create various effects in Viewport 2.0. The Maya Developer Help Viewport 2.0 API section provides information on the classes and methods available for use with Viewport 2.0, as well as information on how to update your plug-in from using the legacy viewport API to using the Viewport 2.0 API.
For more information about how to use the Maya Viewport 2.0 API to port your legacy code to the latest Maya viewport technology see the Viewport 2.0 API Porting Guide and whitepapers, which can be found at http://www.autodesk.com/developmaya.
You have a choice of four rendering engines in Viewport 2.0: OpenGL - Legacy, DirectX 11, OpenGL- Core Profile (Compatibility) and OpenGL - Core Profile (Strict).
Select Window > Settings/Preferences > Preferences to open the Preferences window. Then select the Display category and then your Rendering engine under the Viewport 2.0 section.
Selecting DirectX 11 as your rendering engine lets you render DX11 hardware shaders in real-time in the viewport. See Run Viewport 2.0 in DirectX 11 mode for more information.
Selecting OpenGL- Core Profile (Compatibility) or OpenGL - Core Profile (Strict) as your rendering engine lets you create custom GLSL (OpenGL Shading Language) shaders which support lighting, textures, shadows, and tessellation. See Run Viewport 2.0 in Core Profile mode.
See also Rendering engine (in the Viewport 2.0 Options) for more information.