MDN web docs
Newest ECMAScript Docs: https://tc39.es/ecma262/#sec-fundamental-objects
Video based tutorials have gained huge popularity in recent years. This form of studying is known as the easiest and really effective, so the huge increase in popularity is understandable. Udemy is a great online learning platform with a wide range of courses. It doesn’t only have videos, online tests, zip packages with source code and community conversations are a huge part of Udemy success. There are some free courses, but the better ones are paid. The prices are really high, but you can encounter 90% discounts almost every two weeks.
Some valuable udemy courses:
Learning by doing is pretty good, but if you ask me, learning by doing and competing is just amazing! Codewars is an online learning site, where you can complete challenges, get points for it and compare your solution to others. The challenges are divided into different levels of expertise and your account has a level itself to give you proper tasks. You can get better by completing challenges, but the amount of knowledge gained through studying solutions made by more advanced people is huge. Some code pieces you will find there will change your way of thinking and present you unthinkable actions. You can’t miss codewars!
W3Schools is an old-school tutorial page. You can start your web development path using this webpage, but you will run out of resources quickly. Topics are explained quite well for beginners, but explanations are simple and minimalistic. Lack of crucial topics are enough to say W3Schools is insufficient for more advanced people. Nevertheless, this webpage is worth checking.
It is an unlimited source of knowledge. You can find a huge amount of tutorials, explanations and examples on youtube. Some youtubers even upload some of their content from Udemy, so it is good to pay attention to several channels. I personally really enjoy crash courses on youtube, you can choose some technology and get essentials in under two hours.
Fun Fun Function: https://www.youtube.com/channel/UCO1cgjhGzsSYb1rsB4bFe4Q
Traversy Media: https://www.youtube.com/user/TechGuyWeb
Udemy Tech: https://www.youtube.com/channel/UCU6e4MJtvlcX5DBLP1cq8hQ
Dev Ed: https://www.youtube.com/channel/UClb90NQQcskPUGDIXsQEz5Q
The Net Ninja: https://www.youtube.com/channel/UCW5YeuERMmlnqo4oq8vwUpg
Most comprehensive docs and tutorials: MDN web docs / ECMAScript docs
Best for beginners: Codecademy