Original User: mzcoyle
I mostly use the python window to test code before putting it in a tool or stand alone script. I find I never only do things once, making one off actions in the python window a waste of time. If you want to know the mostly common arcpy functions in any python code I write; I would have to say all the cursors, describe, FCtoFC and various mapping module calls (MapDocument, ListLayers etc). In my library, it is a rare script indeed that doesn't use one (or even most) of those functions.