An expression is that a hobo travels and works. A vagabond or tramp travels but doesn't work. A bum neither travels nor works. In reality the terms were quite f

An expression is that a hobo travels and works. A vagabond or tramp travels but doesn't work. A bum neither travels nor works. In reality the terms were quite fluid. A hobo might have been "on the bum" meaning he couldn't find work and was begging.