what is mac's version of word ?

If you are looking for the apple word processing/ desktop publishing it's Pages which it typically a part of the iWork suite which includes Keynote (presentation) and Numbers (spreadsheet). They can all export into Office.

http://www.microsoft.com/mac/word

Stedman

LibreOffice, free and packed full of goodness.

There is Word for the Mac, but like ds store, I am a fan of free/open-source projects like LibreOffice, Bean, etc.