Why is categorizing an important skill for historians to practice? give an example of how a historian might use categorization to study the past?

Categorizing is a procedure by which a person arranges concepts,ideas or objects into different divisions.By this means, one can be certain about discriminating ,comprehending and establishing relationships between the concepts or ideas.

Categorizing is an important skill for historians to practice since it is meaningful to find connections among the historical events and also crucial to  see the differences among them so as to finally understand them fully. It also serves the purpose of remembering the historical events better.

For instance, a historian when studying a historical event might want to identify the causes and consequences so categorizing them would be very helpful in order to understand the nature of the historical event completely.

map scale refers to the relationship (or ratio) between distance on a map and the corresponding distance on the ground. for example, on a 1: 100000 scale map, 1cm on the map equals 1km on the ground.

i see, would you mind putting it as one?