Explanatory (adjective)

1. Serving to explain or make something clear.
2. Providing an explanation or reason for something.

Origin:

Late 16th century: from latin expositorius (from exponere "explain") + -y.

Examples:

1. The teacher provided an explanatory example.
2. The graph was accompanied by an explanatory note.
3. The article included explanatory details.
4. The manual was written in a clear and explanatory manner.
5. The report was explanatory and provided a lot of information on the topic.