Javascript closures are very hard to get. I didn’t even know how to use them or what they were. The links for the bottom graphic calculator are done with closures used in a loop (at least when I wrote the js file in Prototype). These videos however spell it out very easy for you to understand the concept. From Stuart Langridge’s “Secrets of Javascript Closures” presentation.

Secrets of JavaScript Closures, the presentation, part 1

Secrets of JavaScript Closures, the presentation, part 2

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