3D view allows seeing Second Life, walking and contacting other residents. 3D view is currently in development and its features are extended with every update.
There are two versions of 3D view:
"Gold" - the most advanced version, available for Gold avatars;
"Free" - one version behind Gold. Available to Free avatars. Compare Gold 3D and Free 3D features
The following articles relate to 3D:
To access Gold 3D features, upgrade your avatar to Gold Facility.