Question: What media type should you use for JavaScript source code? Answer [via Brendan Eich] and explanations after the break.

JSON is a plain text data storage format. This blog post describes what it is and how to work with it via an ECMAScript 5 API.

Array.prototype contains many generic methods that can be applied to array-like objects. [] is a popular shortcut for accessing these methods. This post examines the pros and cons of using that shortcut.

Update: Inspired by a comment from Kevin Roberts, I’ve added a third way of accessing generic methods, and a conclusion.

With so many JavaScript implementations out there, how do you guarantee that all of them stay true to ECMA-262 (the ECMAScript language standard)? The answer is test262, a suite of tests to be run by an implementation. Quote from the test262 website:

Update 2014-05-08. Newer version of this post: “ECMAScript 6’s new array methods”

On July 9th, Brendan Eich announced that Rick Waldron had prototyped [1] two new methods for ECMAScript.next: Array.from() and Array.of(). Both methods are also useful in current JavaScript.

Update 2012-10-29: “Properties in JavaScript” is a general introduction to how properties work.

This post examines how inheritance and enumerability affect operations on properties in JavaScript.

This post lists several benefits of taking a break during programming.

Update 2011-09-16: Source maps are coming to WebKit, too. Mozilla and WebKit implementers might even agree on a common format.

More and more languages are compiled to JavaScript. Mozilla has plans to let you debug those languages in their source code (no need to look at JavaScript).

This blog post explains the difference between JavaScript and ECMAScript. And the differences between ECMAScript.next, ECMAScript 6 and ECMAScript Harmony.

Updates – read first:

• [2011-11-04] “Myth: JavaScript needs classes” introduces a more concise name for “prototypes as classes”: object exemplars. An exemplar is a factory for instances, constructors are function exemplars.
• [2012-01-08] “JavaScript inheritance by example” is a more hands-on introduction, complementing this post.
• [2012-07-29] Classes have been accepted for ECMAScript.next.
• [2012-10-03] Since this article has been written, it was decided that ECMAScript will have the special property __proto__ instead of the <| operator.

JavaScript’s prototypal inheritance is hard to understand, especially for people coming from other languages that are used to classes. This post explains that it does not have to be that way: The proposal “prototypes as classes” is a simplification of classes and inheritance in JavaScript. It might become part of ECMAScript.next, a.k.a. “the next version of JavaScript” (after ECMAScript 5). But there is also a library that allows you to use its features in today’s JavaScript. What’s intriguing about prototypes as classes is that they aren’t a radical departure from current practices, but rather a clarification of them.

Incidentally, this post is also a good introduction to JavaScript inheritance, because the basics are easier to understand with prototypes as classes.