# 11B Explaining How the Pieces Fit Together

A good explanation of an implementation describes responsibilities and relationships before going through every line of a long function.
Suppose that the application shows a list of lessons, and each lesson has a title, an image, and a short description.
One module retrieves the data, another prepares the display values, and a component renders the information that the user sees.
The file containing the query may be different from the file containing the markup, even though both affect the same page.
If an image is missing, we need to understand whether the stored path is empty or the rendering logic uses it incorrectly.
These possibilities suggest different changes, so locating the visible component alone may not identify the actual source of the problem.
I prefer examples that follow one piece of data through the relevant functions and explain what each step adds or changes.
Technical names are useful when they identify a specific object, but the explanation should also describe its role in ordinary language.
A simple diagram or a short sequence can sometimes explain the relationship more clearly than a large block of copied code.
Once the connection is clear, we can discuss the change without treating the whole project as one mysterious and inseparable system.