Or as Cyril J Wood states in the intro to his book.
Let’s get one thing straight from the start… as the title of this eBook and website points out… a narrowboat is not a barge. A narrowboat, as its name suggests is narrow, having a beam (width) of 6 foot 10 inches to 7 feet. Canal barges are between 60 and 70 feet in length depending on the canal they were built for. However, they are at least 14 feet 6 inches beam, are usually used for carrying cargo and are made from steel, wood or even concrete. Neither is a narrowboat a longboat. Longboats were what the Vikings used to convey them on their raping and pillaging voyages of discovery in the Dark Ages. The unenlightened amongst us will quite often confuse the three terms, much to the annoyance of narrowboat owners, canal enthusiasts and boat anoraks in general.