What is Visual Basic for Applications (VBA) and how does it fit in?

VBA is a version of Visual Basic 6.0 that is used as an internal programming language in many other systems such as Microsoft Office programs like Word and Excel. (Earlier versions of Visual Basic were used with earlier versions of Office.) Many other companies in addition to Microsoft have used VBA to add programming ability to their own systems. VBA makes it possible for another system, like Excel, to run a program internally and provide what is essentially a custom version of Excel for a particular purpose. For example, a program could be written in VBA that will make Excel create an accounting balance sheet using a series of accounting entries in a spreadsheet at the click of a button.

VBA is the only version of VB 6 that is still sold and supported by Microsoft and only as an internal component of Office programs. Microsoft is developing a completely .NET capability (called VSTO, Visual Studio Tools for Office) but VBA continues to be used.