Undo scope
A sequence of undo units that are marked with a beginning and an end.
Undo stack
A region of reserved memory where undo units are stored.
Undo unit
An instance of a class that encapsulates the information that is necessary to reverse an action made by a user in the user interface or an Automation client.
Universal name
The name for any shape, master, page, style, row, or layer used by Automation clients; objects may also have local names that are used in localized versions of an Automation solution. Universal names allow source code to remain unchanged for localized versions.
Unscaled drawing page
A drawing page whose drawing scale is 1:1.
User form
A file in a Microsoft® Visual Basic® or Visual Basic for Applications (VBA) project with the file name extension .frm that contains user interface controls, such as command buttons and text boxes.
Vertex
One of the diamond-shaped handles that appear between two segments on a multiple-segment shape, or at the end of a segment. You can reshape a shape or connector by dragging its vertices.
Visio add-on
See add-on.
Visio library
A special dynamic-link library (dll) that is loaded by Microsoft® Visio® at run time and can implement one or more Visio add-ons. A Visio library has the .vsl file name extension.
Visio type library
A file that contains definitions of the objects, properties, methods, events, and constants that Microsoft Visio exposes to Automation.
Walking glue
A type of glue behavior in which the endpoint of a connector can move from one connection point to another as the connected shapes are moved. More commonly known as dynamic glue.
Width-height box
A rectangle orthogonal to a shape's local coordinate space with one corner at (0,0) and its opposite corner at (width,height).
Wizard
An add-on that prompts the user for information to automate specific tasks.
Workspace list
A list saved with a drawing, template, or stencil file that identifies the names of documents and windows to be opened, as well as the type, size, and location of the windows, based on their appearance when the file is saved.