Data,

no not the character in Star Trek,

think raw data that the collector wishes to show in an easily explainable way to others, as in processed data, I came across these examples on the DataArt site, the one above by Charles de Fourcroy, TableauPoléometrique, he was a French mathematician who produced this visual analysis of urban growth in French cities,

Dr. John Snow’s map of cholera deaths in London that helped in combating the disease in the second half of the 19th century, his question was why did a lady washing a nappy in a well cause the deaths of 616 people? and what was the connection to the huge number of deaths from cholera in the 1800s in London? strangely enough the problem was solved by Sir Joseph William Bazalgette, but that is another story,

keeping to a slightly macabre piece of data, a polar chart by Florence Nightingale showing the deaths from diseases verses wounds, 

and a 3D graph of the population of Sweden 1750-1875, by Luigi Perozzo, who would have thought data could be so interesting and almost a work of art.