Ever since the second UK Census was taken, just over two centuries ago in 1811, this 10-yearly survey of the entire population became interesting because one Census could be compared to the previous Census to see how the population had altered in number, and later, as Censuses became more sophisticated, in its characteristics. Without the ability to compare and contrast, very big or very small numbers have limited significance. And to see any significance of a large volume of numbers relating to many areas it helps to map them. Very little mapping of Census data was done, however, until it became possible to use computers to both tabulate and aggregate Census data, and also to draw the numerous possible maps that could be produced. Automation also turned out to be vital, along with the development of new computer algorithms. These were needed to reorder space itself, creating new map projections that are required if most Census data is to be seen at all clearly and if the rest is to be seen undistorted. Until the 1960s almost all mapping of Census data that was conducted was undertaken by hand, and Census maps were drawn using map projections in which the information about most of the population was hidden in just a few small densely populated places on the map.