6 items
Extending Array.prototype Safely
Where Array Methods Live
Prototypes Behind Array Methods
Prototypes, this & ES6 Classes
What Is a Prototype?
Understand why arrays can call methods like map even though you never defined them.
You create const arr = [1, 2, 3] and call arr.map(x => x * 2). The array literal has no map property directly on it. How does JavaScript resolve arr.map?