There are a ton of websites that offer information about JavaScript. Some are ok, some are good, some are great. These are the ten websites that I feel offer great information about JavaScript.
This list will change often.
Mozilla Developer Network
MDN JavaScript Home
MDN JavaScript Search
Mozilla describes themselves as: “…a proudly non-profit organization dedicated to keeping the power of the Web in people’s hands.” I believe it, and I believe in them. They have created a ton of helpful articles on JavaScript that are worth their weight in gold.
SitePoint
sitepoint.com
Sitepoint articles are always informative and well-written. It surprises me how actively this site is updated.
Codecademy
codecademy.com
If interactive instruction is your thing, then Codecademy is a great place to dive-in. The interface is clean and the content is quite good.
JavaScript-Garden
http://bonsaiden.github.io/JavaScript-Garden
It’s a bit odd how all of their JavaScript content is one one page. That said, it is a page jam-packed with solid content that addresses some of the most common JavaScript topics that web-developers often find confusing.
javascript.info
http://javascript.info
The coverage is somewhat brief, but overall well-done. The author is Russian and gave-up on the English version of this site because of his frustration with English. There is a link to the Russian version of the site, which offers a great deal of content and is actively updated. If you use Google Chrome, then you can translate these pages on the fly.
Impressive Webs
impressivewebs.com
If you are passionate about JavaScript, this is an excellent resource. There is a nice balance of core JavaScript cocepts and articles about advanced topics.
JavaScript Weekly Archives
javascriptweekly.com
The main goal is to sign-up for the weekly email newsletter. But, you can also just browse past issues. Either way, javascriptweekly.com is a great resource for JavaScript enthusiasts.