A major disadvantage of the file type is its lack of portability. The file extension has undergone a number of revisions, from version 3.0 for Windows 95 up to the current version 14 used by Microsoft Publisher 2010. Microsoft Publisher files may contain various elements including images, graphics, formatted text and objects. PUB to DOC - Convert file now View other document file formats The file type is typically used for amateur publishing with professionals opting for higher end file types. pub file can contain images, graphics, formatted text and other objects. pub file extension is the file extension used by the Microsoft Publisher application which forms part of the Microsoft Office product set.