Office 2007 will have a new, XML-based file format for Microsoft Word 2007, Microsoft Office Excel 2007 and Microsoft Office PowerPoint 2007. The New file formats will be the default file formats for Office 2007 but they will also be backward compatible to Microsoft Office 2000 using Office 2007 Compatibility Mode.
Here are the new file formats
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Word 2007 Supported File Formats
Word Document (.docx) - Default format
Word Macro-enabled Document (.docm)
Word Template (.dotx)
Word Macro-enabled Document Template (.dotm)
Excel 2007 Supported File Formats
Excel Workbook (.xlsx) - Default format
Excel Macro-enabled Workbook (.xlsm)
Excel Template (.xltx)
Excel Macro-enabled Workbook Template (.xltm)
Excel Binary Workbook (.xlsb)
Excel Add-in (.xlam)
PowerPoint 2007 Supported File Formats
PowerPoint Presentation (.pptx) - Default format
PowerPoint Macro-enabled Presentation (.pptm)
PowerPoint Slide Show (.ppsx)
PowerPoint Macro-enabled Slide Show (.ppsx)
PowerPoint Template (.potx)
PowerPoint Macro-enabled Presentation Template (.potm)
PowerPoint Add-in (.ppam)
Word Document (.docx) - Default format
Word Macro-enabled Document (.docm)
Word Template (.dotx)
Word Macro-enabled Document Template (.dotm)
Excel 2007 Supported File Formats
Excel Workbook (.xlsx) - Default format
Excel Macro-enabled Workbook (.xlsm)
Excel Template (.xltx)
Excel Macro-enabled Workbook Template (.xltm)
Excel Binary Workbook (.xlsb)
Excel Add-in (.xlam)
PowerPoint 2007 Supported File Formats
PowerPoint Presentation (.pptx) - Default format
PowerPoint Macro-enabled Presentation (.pptm)
PowerPoint Slide Show (.ppsx)
PowerPoint Macro-enabled Slide Show (.ppsx)
PowerPoint Template (.potx)
PowerPoint Macro-enabled Presentation Template (.potm)
PowerPoint Add-in (.ppam)
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