@JorgeV
Good list, but I would caution on a view points.
W3Schools - [w3schools.com...]
To me, the ultimate site for webmasters (HTML, CSS, JavaScript, PHP, ASP, Node.js, Python, Java,...).
Ultimate is a bit much, it is great for HTML and CSS for sure. JS is okay but I find that
Mozilla is much better [
developer.mozilla.org...] It is far more technical but I feel that that is required for a language like JS. I can't really speak to PHP, since I have never really coded in PHP, but I've used it (w3schools) a few times and it helped when I needed it. ASP NODE and Java I have never touched.
As for Python, I think W3schools is horrible for it. The best resource for Python is docs [
docs.python.org...] any and all information is there clearly written, comprehensive and includes example code. If I have questions beyond the docs then I go to
stack overflow.
CSS-Tricks - [css-tricks.com...]
This site has helped many times.
W3C Markup Validation Service - [validator.w3.org...]
Again great resource, but in my situation, where I deal with dynamic pages that are multi-language templates I find that it tends not to be very helpful. But at times situations arise where one needs to be sure that a section of code or rendered page is valid and then it is definitely indispensable.
JSFiddle - [jsfiddle.net...]
Lover it, I use it a lot when I'm trying new stuff in JS. It is great to build a quick mock-up and then share it with others. Or to help others solve bugs, like in forums here.
WebmasterWorld I doubt I need to say more, but again an indispensable resource.
stackoverflow.com - [
stackoverflow.com...]
This is without a doubt the single most valuable resource on the web, it has provided me with solutions to problems from the most simple mind farts to the most complex and obscure issues for a wide range of programming languages, from Lego(MindStorm) to TensorFlow.
