The Visio Corporation originally developed Visio and released it in 1992. Microsoft acquired the company in 2000. The latest release is Visio 2007. To use Visio, you start by choosing a specific template. Visio offers a large collection of templates in categories such as Business, Engineering, Flowchart, Maps and Floor Plans. Basing the drawing features on templates eases the work, as most of the graphics, based on conventions and standards, are drawn by the program. The user needs only to enter specifics that are unique to the project. The template categories cover most diagramming needs quite well. Each category of templates has a range of templates. You can easily find a template that suits your situation.
The Business category has brainstorming diagrams (mind maps), organization charts, pivot diagram, audit diagram, basic flowchart, cause and effect diagram (Pareto diagrams), charts & graphs, cross functional flowcharts, data flow diagram, data flow diagram, EPC diagram, fault tree analysis diagram, ITIL diagram (using ITIL library), marketing charts and diagrams, an organization chart wizard, TQM map, value stream map and work flow diagram. Have they missed a category that you may need in business use? I cannot think of any.
The Engineering group contains basic electrical, circuits and logic, fluid power, industrial control systems, part and assembly drawing, piping and instrumentation diagram, process flow diagrams and systems. Once again, you can obviously go further with full-fledged CAD software packages. However, you would not need them at the proposal stage or for bid documents and such business related uses.
The Flowchart templates group is a collection of different kinds of flowcharts. The general group has general and basic flowcharts including block diagrams. The Maps and Floor Plans group covers different kinds of floor plans that you may need including site plan. The Network group includes templates for simple network plan and network architecture diagram etc. In the Schedule group, you have the calendar, Gantt chart, PERT charts and timeline diagrams. Software and Database templates include the templates one may use in various software development scenarios and database planning situations. You can view examples of these templates in the photo gallery.

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