Chapter 5 Map Scale and Generalization Concepts Scale Scale is the relationship between distance on the map and distance on the ground. Selecting the appropriate scale depends on the size of the sheet of paper and the accurate placement of features.
Watch out for maps that have been reproduced and have had their scale changed. A graphic scale will change with the reduction or enlargement but the other scales become wrong.
When map don’t have scale on map, then:
Map scales can be converted from one form to another
"The process of generalization requires the selection of those features that are essential to the map's purpose and the representation of them in a way which is clear and informative".