what is the "AutoCAD standard version" ?

I suppose you could say the "standard" version is the basic full version of AutoCAD.  There is another version called AutoCAD LT that does not include 3D functions, the Express Tools, Parametric definitions (geometric and dimensional), LISP and other feature in the full version.  But other than that it is the same program.
 
This is what we normally refer to as the "full version" of AutoCAD.  All of the Autodesk vertical products like Architecture, MEP, Civil 3D, Electrical, Revit, and others are built on top of this basic "full version" of AutoCAD.
 
Hope that answers the question.
 
Dave.