It is the first book that has actually explained the "why" of using a Java interface to me (Rather than the usual "how").
To most of you, this may seem trivial. However, this brings up a bigger point that I have noticed: Not all books (Or people) can teach or explain a concept in a concise, easy to understand manner.
As such, it is a rare gem when I find a book that can explain the "why" of a concept rather than just throw pages upon pages of filler at you.
Today, this book has given me a superpower of finally understanding just how interfaces work. Tomorrow, others may benefit from me (Hopefully) writing better code.
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