ABSTRACT
THE BEST PLACE TO START learning about data vi-sualization is with quantitative variables. By quantitative, Imean that they can take a range of numeric values that measure something in the real world. We can split them further into continuous variables and discrete variables. Continuous variables can take a very precise value to many decimal places, at least in theory. Discrete variables can only take particular values, usually 0, 1, 2, 3... (what mathematicians call natural numbers).
