Check out a free preview of the full Advanced JS Fundamentals to jQuery & Pure DOM Scripting course:
The "Visually Understanding Closures and Call Objects" Lesson is part of the full, Advanced JS Fundamentals to jQuery & Pure DOM Scripting course featured in this preview video. Here's what you'd learn in this lesson:

Using a closure that returns a counter, Justin demonstrates how subsequent calls to the function affect the returned data. Functions always have a references to call-object where they were created.

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