Open 3DD File
The 3DD file is a type of GIS data file created by ArcGlobe, a viewing application used to view GIS data sets in 3D.
ArcGlobe is basically a 3D map viewer application that allows you to view large amounts of GIS data on the surface of a globe, it comes bundled with ArcGIS Desktop.
ArcGlobe provides an innovative way to view and analyze GIS data.
Spatially referenced data is placed on a 3D globe surface, displayed in its true global geodetic location.
In this particular case, a 3DD file stores a reference and connection to a geodatabase, which contains the spatial content and output results created by the software's geoprocessing operations.
The 3DD extension file can store GIS data as a collection of three-dimensional layers.
The 3DD file is used to save and load views of 3D GIS datasets.