VSD, Microsoft Visio Drawing File (.vsd)
The VSD Vector image file format
The VSD file extension was originally developed by Microsoft as part of its Visio product. Visio is one of the products included in the Microsoft Office suite of products and it gives you the ability to create business diagrams that can be very advanced in nature. Visio is considered a diagramming and vector graphic application and the pages created with said program can include data, text, various information flows, and different types of visual objects that help those pages come to life and simplify (or showcase) the information being presented. Visio drawings with the VSD extension make it easier to present and record complex information through diagrams, organizational charts, and complicated flowcharts.
Technical details of VSD files
The VSD file extension was originally created by the Shapeware corporation in 1992. It was later made part of the Microsoft Visio product line and became a part of Microsoft Office. VSD is an XML schema based format and it is a proprietary binary file format. It uses the lossless compression method. In 2013, Microsoft replaced the VSD file format in all of its Visio products with VSDX and VSDM files, thus it is no longer being actively used. If you have Visio software, the VSD files should still be able to be used, however there may be instances when you need to convert the VSD file that is giving you problems.