Vector graphic (Professional Draw)
The GSD file extension is used for a vector graphics image format developed by GraphTec. GSD files are used to create cutting templates so the company can produce adhesives, laminates, and other products. It seems to be a proprietary format used only by GraphTec; it was previously associated with Professional Draw, which was developed by the now-defunct Gold Disk.
In non-graphics uses, the GSD extension is an option for GSplit, a free application that splits a large file into a set of smaller files.
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Visit the GraphTec web site.
Visit the GSplit home page.