PRC (Product Representation Compact) is a 3D file format that can be used to embed 3D data in a PDF file. This highly compressed format facilitates the storage of different representations of a 3D model. For example, you can save only a visual representation that consists of polygons (a tessellation), or you can save the model's exact geometry (B-rep data). Varying levels of compression can be applied to the 3D CAD data when it is converted to the PRC format using Adobe Acrobat 3D.
Dolby Digital film format, developed for encoding audio tracks for films. It supports up to 6 audio channels: left, right, front, rear, upper and lower. Because of this, it allows you to store “3-dimensional” audio tracks. It’s widely used both in movie theaters and by the users themselves for storing audio tracks in film libraries at home.