Read and Write Open XML Files in MS Office 2007
By Zeljkos
Introduction
With Office 2007, Microsoft decided to change default application formats from the old, proprietary, closed formats (DOC, XLS, and PPT) to new, open and, standardized XML formats (DOCX, XLSX, and PPTX). New formats share some similarities with old Office XML formats (WordML, SpreadsheetML) and some similarities with competing OpenOffice.org OpenDocument formats, but there are many differences. Because new formats will be the default in Office 2007, and Microsoft Office is the most predominant office suite, these formats are destined to be popular and you will probably have to deal with them sooner or later.