Portable Document Format (PDF) is a type of document created by Adobe back in 1990s. The purpose of this file format was to introduce a standard for representation of documents and other reference material in a format that is independent of application software, hardware as well as Operating System. PDF files can be opened in Adobe Acrobat Reader/Writer as well in most modern browsers like Chrome, Safari, Firefox via extensions/plug-ins.
3DS3D Studio Mesh File Format
A file with 3DS extension represents 3D Sudio (DOS) mesh file format used by Autodesk 3D Studio. Autodesk 3D Studio has been in 3D file format market since 1990s and has now evolved to 3D Studio MAX for working with 3D modeling, animation and rendering. A 3DS file contains data for 3D representation of scenes and images and is one of the popular file formats for 3D data import and export.