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*Details: File format summary



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Name Microsoft Office Open XML
Version 2007 onwards
Other names  
Identifiers PUID:  fmt/189
Classification Aggregate
Description Microsoft developed office Open XML (OOXML) in 2007. It is an XML based format representing a departure from previous Microsoft Office suites, which were binary file based. Starting with Microsoft Office 2007, the Office Open XML file formats have become the default file format of Microsoft Office. The ISO standard for OOXML is ISO/IEC DIS 29500. An OOXML file format consists of a compressed zip archive that is designated according to which file type it is. OOXML uses three custom XML based languages to describe its’ three document types. WordProcessingML, SpreadsheetML and PresentationML are each used to describe Word, Excel and PowerPoint Presentation files respectively. OOXML is not an open format but the specification and development rights have been released under Microsoft’s Covenant not to Sue. OOXML is platform independent.
Orientation Binary
Byte order  
Related file formats Has priority over ZIP Format  
Technical Environment  
Supported until  
Format Risk  
Developed by Microsoft Corporation
Supported by Microsoft Corporation
Source Digital Preservation Department / The National Archives
Source date 06 Oct 2009
Source description  
Last updated 06 Oct 2009
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