VSS is stencil files created with Microsoft Visio 2007 and earlier. A relatively new file format is VSSX that was introduced with Microsoft Visio 2013. Stencil files provide drawing objects that can be included in a VSD Visio drawing. Microsoft Visio is used for creating drawing elements such as a collection of shapes, connectors, flowcharts, network layout, UML diagrams, software diagrams, database models, objects mapping, and other similar information.
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