The ".pub" file extension is associated with the "Publisher" application included in recent versions of Microsoft Office. Once a *.pub file has been opened in publisher, it can be re-saved as a web page or other format using the "Save As" command and selecting the desired format under the "Save as type:" drop down menu.
PUB must be opened in a publisher software, without Office you could use a similar program like OpenOffice. If not you will need to converted to PDF or DOC with a third party software.
They are named with a .doc extension in versions up to Word 2003 and .docx extension since version Word 2007.
.PUB
".doc" in versions of Microsoft Word before 2007".docx" in Microsoft Word 2007 and later..docMS word
doc, DOC
.doc just say hey I'm a old word processing file extension and this is how I need to be opened, so you can read me.
Doc file extension is short for document
.doc or .docx
.doc
.doc , .docx
It is a Microsoft Publisher file.
the Microsoft word files are called document