Between all of the ships that once roamed the galaxy, there had always been many differences that made each one unique. Although very different, there was one thing that most star-ships had in common. The use of waste collection droids.
Waste collection droids were used in many ways on past ships. The first and main thing that these droids did was pick up after the inhabitants of the ships. They were only programmed to take and follow orders given to them by their owners. This made them seemingly flawless. Next, these droids were used to enter, and work in places too dangerous for other organic lifeforms. The last and least common thing that these droids used to do was lift heavy things. This was very easy for the droids to do since the were over 6 feet tall.
In all of the past years when these droids were used, they became more and more commonly seen among working and leisure class ships. They made many traveler's lives easier.