The Millennium Falcon was always described as a freighter converted to a smuggler. But from the beginning, fans wondered how it could have been a freighter when it is obvious that there is no space in the ship for a significant cargo hold. Eventually, someone arrived at the idea that the Falcon didn't carry cargo, it pushed it as do pusher tugs (also called towboats) on major rivers. This was partly inspired by the "mandibles" on the front of the Falcon that look like they might be intended to grip something. Over time, a number of designs were created that suggest how it would look for the Falcon to push a string of cargo containers, such as this one.