An example suggests one member of a class of objects to convey an accurate impression of the entire class. Graphics provide a pictorial representation where lines, dots, arrows, etc. are configured into representational patterns. Comparisons and contrasts suggest ways in which objects or conclends are similar to or different from one another. An elimination indicates what something is not to clarify what it is. An etymology explores the origin and historical development of a word.
History records the events in the development of something.