Navigation.

Creating a simple and easy to use interface is always the one of the most important aspects of a successful application. It has to be easy to use and not confuse the user with ugly, unnecessary and complicated graphics. Also, the interface should be cleaver and deliver only what the user asks for.

The task of navigation is the most prevalent user action in most large 3D environments, and it opens some challenges such as supporting spatial awareness, providing efficient and comfortable movements between distant locations (e.g. room to room or floor to floor or building to building) and making navigation lightweight and fluid so that users can concentrate on more important tasks.

“Navigation is subdivided into 2 components, the motor component called “travel” and the cognitive component called “wayfinding”. Navigation tasks can be classified into three catagories; Exploration - user investigating target locations
Search - moving to a particular target location
Maneuvering - moving to a viewpoint at a more advantageous
for performing a particular task.”