OpenDocument Graphic File
The OpenDocument specification is file format based on xml and is used for documents, spread sheets, presentations and charts. It was originally developed by Sun Microsystems but the actual standard was developed by the Organization for the Advancement of Structured Information Standards(OASIS). OpenDocument is also an ISO/IEC standard ISO/IEC 26300:2006 Open Document Format for Office Applications (OpenDocument) v1.0.
Drawings using vector graphics that have been saved in this format make use of the .odg file extension which shows that the file is an OpenDocument graphic file.