Also, if you're learning Ruby, Python, and eventually JS you're going to have to pick up HTML and CSS on the side.
HTML and CSS so perfect and beautiful, right until the point where your website looks like it's melted in Opera, Firefox, Safari, Chrome or IE.
There are some HTML and CSS cookbooks that do all right, but it's borderline impossible to get a grasp over the whole thing.
It's composed entirely of mangled versions of ancient official documentation, corrupted with hearsay, riddled with content-styled ads, and scummily trading on the name of the bureaucrats that attempt to be authoritative on the whole mess. Every single example he provides manages to be a horrifying implementation of 'worst practice'.
http://www.quirksmode.org/compatibility.html is the browser reference you want.
For backend stuff, go to the upstream developers, not some bullshit artist that's manage to paraphrase and SEO his way to being king of the shitpile.
A developer (read anyone with sufficient technical background and experience to actually write code) doesn't need or want the kind of shit that site is peddling. But for someone with zero technical background the site actually does a pretty good job of providing enough of an introduction for someone to get a toehold on the material.
Also, very few common/good practice parts.