As you open a Visio document, you may want to add more SmartShapes or images. Visio parades a wide variety of themed-based Stencils that you can open at any time, even if they don't associate to the specific Visio template where your document originated. Figure 3.7 shows a visual opening the Stencil drop down button.
A Stencil file can be opened in the following ways:
From the File menu, choose the Stencils command.
If you are looking for a specific Stencil, roll your mouse over or click one of the Visio Template categories, and choose a Stencil file.