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Pptx is a new presentation format that was introduced by Microsoft in Microsoft Office 2007. It replaced .Ppt as the standard format of Microsoft PowerPoint Presentations. Pptx is based on the new standard for Office files(spreadsheets, word processing documents, presentations etc) called Office Open XML, which replaced the previous binary and 2003 XML formats.
Pptx files cannot be opened in older versions of Microsoft Office without prior conversion to Ppt format.
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