Yes, absolutely.
yes
Yes they are compatible! OpenOffice.org reads Microsoft office files fine, including the older office 2003 formats, and the newer xml based (2007+) ones. There maybe a few odd formatting things you need to tweek if you save from openoffice.org to Microsoft office, but generally it works fairly well. If you want the best compatibility, then try go-oo, a fork of openoffice that has better compatibility, even with stuff like Microsoft VBA macros. So yes, it works fine. And of course, openoffice always works better on Linux! Also, don't forget when saving to change 'odf' to Microsoft office. But you can change the default save format to msoffice if your using it frequently
Yes. DOCM is a Word Microsoft Office Open XML Format document. It is opened by default by Word 2007 upwards. For earlier versions of Word (2003 and below), you'll have to download the Microsoft Office Compatibility Pack for free from Microsoft's website.
No, software is rarely 'backwards compatible' - Office 2007 should be happy to work with version 2003 files, but Office 2003 will likely reject 2007 files, due to it not being capable of understanding enhancements made after the Office 2003 software was written.
DOC - is a text document that can be opened and edited with MS Word or OpenOffice. RAR - is an archive that can be opened with an archiver tool, B1 Free Archiver foe example.
First you would have to have Microsoft Publisher in order to view or edit .pub files. The program Microsoft Publisher can be opened by going to Start->All Programs->Microsoft Office->Microsoft Publisher.
If the document from the Mac has been saved in a format recognised by Word then it can be opened by Word. There are variations in different versions of Word which means that sometimes even Word cannot open a Word document.
since XLS and XLSX are proprietary formats of Microsoft products, I'm not sure there is a (free) PHP way to do so. you can export your data in CSV, which is easily opened in Microsoft Excel or OpenOffice Calc
Microsoft Office 2010 installs plugin in Firebox web browser which allows documents to be opened directly from web browser into the appropriate Office desktop application.
DOCX files can be opened using various programs, with the most common being Microsoft Word. Other options include free alternatives like Google Docs, LibreOffice Writer, and OpenOffice Writer. Additionally, many text editors and document viewers, such as WPS Office and Apple Pages, also support DOCX files. Online converters and viewers can also allow access to DOCX content without needing specific software.
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.
Normally it will update automatically. If it is linked into another document, it may have to wait until it is that document is opened before updating.