The primary difference between the standard and professional editions is the kinds of drawings you can make. Both editions come with templates to help you get started. The professional edition has templates for more kinds of drawings.
The standard editions are designed to work with basic business diagrams, basic flowcharts, organization charts, and multipurpose drawings. Templates are included for these kinds of basic drawings, but not for the more advanced kinds of drawing named in the next paragraph.
The professional editions are designed to create more advanced types of drawings, such as engineering schematics, floor plans, advanced process diagrams, logical network layouts, software mapping, and database modeling. Templates are included for basic drawings and advanced drawings. Tools for collaboration and for linking data to your drawings are also included.
What is Visio?
Microsoft Visio is software for drawing a variety of diagrams. These include flowcharts, org charts, building plans, floor plans, data flow diagrams, process flow diagrams, business process modeling, swimlane diagrams, 3D maps, and many more.
All editions share functionality with MS Office Word and Excel, such as text and color choices, and allow data feeds directly from MS Excel and Access. As with other diagram software, Visio provides a library of templates and shapes for various types of charts to help you get started.