The visualization of this data, and its range of techniques, has changed over time, especially in its movement from an expert to a public act. Data began to be explained to a widening audience to shape its behaviours and its institutions.
The use of data in education systems and the procedures by which the data are constructed has not been a major part of the study of education, nor of the histories of education systems. This volume of contributions, drawn from different times and spaces in education, will be a useful contribution to comparative historical studies.