Codeacademy
Many new coders get their start here
Interactive learning: read a bit, type your code into the browser, see results immediately
Offer lessons in: HTML, CSS, Javascript, Python, etc
freeCodeCamp
Code taught through established 800 hours total curriculum
Gives hands-on experience by enabling users to work on projects for nonprofits
Good for getting practical, hands-on experience
Offers coding certifications in: HTML, CSS, Javascrpt, jQuery, DevTools, etc
Coursera
All courses taught by university professors
Very wide variety of courses taught
If you want a "Coursera Verifited Certificate," you need to pay $30-$100
edX
Open-source higher education program led by MIT and Harvard affiliates
600 courses in the category of "computer science" offered
Some kinds of courses offered: Java, C#, Python
Codewars
https://learntocodewith.me/posts/code-for-free/