LibreOffice
What is LibreOffice?
LibreOffice is the complete open source office suite
According to Wikipedia, LibreOffice is a free and open source office suite, developed by The Document Foundation. It was forked from OpenOffice.org in 2010, which was an open-sourced version of the earlier StarOffice. You can install it on Microsoft Windows, Mac OSX and it is the productivity suite of choice on most Linux distributions.
LibreOffice.org can be used as a replacement for Microsoft Office.
Visit the LibreOffice.org site to learn more and to get the latest version.