I guess I really don't know the difference. Today I'm adding to my gallery a few whimsical sketches of the old Concord Road Covered Bridge - drawn with one line without raising the pen from the paper (well, I may have cheated just a little).
The question is, are these abstract drawings, or impressionist? Or, perhaps another more pertinent question may be, does it really matter?
I did it just for fun, to see if I could, a few days after I joined some other artists in my first "plein air" experience nearly 9 years ago. So, let me also add my sketch of Shane McDonald painting the real thing, so the viewer can compare.