1. Google Docs
Google Apps can convert Office documents to native Google format, but now it can also edit Office documents directly, as well. There may be some formatting changes if you convert back and forth, but the content should convert pretty well overall. This should probably be your first option for working with Office documents.I find that I do most of my work directly in Google Apps these days. The only time I need to use Word specifically is if I need to do a complex table layout, with merged cells and odd borders. Everything else I can do with Google Docs.
2. Free Alternatives
There are two sets of programs that are free and open-source, and compatible with all Office documents. You can download and install either of these on Windows or Mac computers.- Apache Open Office - www.openoffice.org
- LibreOffice - www.libreoffice.org