Open Packaging Conventions
The Open Packaging Conventions (OPC) is a container-file technology initially created by Microsoft to store a combination of XML and non-XML files that together form a single entity such as an Open XML Paper Specification (OpenXPS) document. OPC-based file formats combine the advantages of leaving the independent file entities embedded in the document intact and resulting in much smaller files compared to normal use of XML. == Specifications == The OPC is specified in Part 2 of the Office Open XML standards ISO/IEC 29500:2008 and ECMA-376.
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