VisualBasic has two components: the Visual and the Basic. When you program VisualBasic, you need to setup both these two halfs. When you create the visual side, you are designing the window, and the interior of the window (e.g. the buttons and the text and picture boxes etc) that you will see when you run your VisualBasic project. These windows are called Forms in VisualBasic.
The Basic component is the actual code that associated with the buttons in the windows/forms, and (stating the obvious) uses the BASIC programming language.
It is important to note that you, the programmer, has to design both the visual and basic aspect of any VisualBasic project. These two components are linked together in a very intuitive way: E.g. Any "command" button on a window/form has Basic code associated with it, so the action of clicking on the button means that the Basic code associated with that button will be run.
VisualBasic has two components: the "Visual" or Form (or Window-like) part, and the "Basic" or code part. The two are linked in a very intuitive fashion.