"Helpful diagrams" refers to visual representations, such as charts or illustrations, that provide assistance or make understanding something easier. Full definition
Here is an excerpt: «The book is filled with helpful diagrams, pictures and algorithms that promote deeper understanding and enable a more pleasant read. (jandaapproach.com)
Using an appealing, approachable, and downright jaunty cartoon style, Wicks playfully yet informatively leads readers through the various systems of the body, clearly explaining basic concepts with both words and helpful diagrams in a perfect balance of engaging silliness and rigorous science. (booklistonline.com)
23 Incredibly Helpful Diagrams For Moms - To - Be. (pearltrees.com)