The wiki for rough states that they are the same thing; for people who have no idea what the equivalent of "rakugaki" (落書き) in English is, tagging would be easier.
Updated by ShadowbladeEdge
Posted under General
What's the difference between sketch and rough supposed to be anyway? Doesn't seem like they're clearly delineated at the moment IMO and haven't used "rough" much (I tend to use "sketch" by default)
i agree too, there seems to be no clear boundary add the fact that sketch has rough_sketch as an alias. it will confuse the people more if we try to separate these 3 tags.
EDIT: topic #10602 seems related