Elementary Statistics (1+1)

5.1.3 Difference between Diagrams and Graphs

Though there is no clear-cut line of demarcation between the two,  following points of difference may be noted.

1. For constructing a graph we generally make use of graph paper whereas a diagram is generally constructed on a plain paper. In other words, a graph represents mathematical relationship (though not necessary functional) between two variables whereas a diagram does not.
2. Diagrams are more attractive to the eyes and as such they  suitable for publicity and propaganda. They do not add anything to the meaning of the data and, therefore, from the point of view of a statistician or research workers they are not helpful in analysis. Graphs, on the other hand, are very much used by the statistician and the research worker in analysis.
3. For representing frequency distributions and time series, graphs are more appropriate than diagrams. In fact, for presenting frequency distributions diagrams are rarely used.