The idea of a visual workplace is important to lean thinking.  After so much time is spent sorting tools, machinery and supplies, it is important to create a space that can accommodate a re-organization of essential and non-essential things.  When tools have been sorted and important ones are to remain in the workplace, it it important to set a sepcific visual spot for each tool to reside, and to identify its location. 

Outlining of the tool is crucial, because that will enable any worker who needs it to find it--and know where to put it at the end of the work shift.  Similarly, workers need a visual cue as to where individual work zones are located without having to spend much time deciphering it.  This is an aspect of lean where the "setting in order" via these visual signals (i.e, floor tapes in various colors) will help workers and visitors alike understand the importance of knowing where everyone, and everything, should be.  No time is then wasted on anything other than the job at hand.