Help
Stack Overflow
A community-run website that provides an outlet for people to ask programming/CS questions.
Learning
Codecademy
A free site that provides interactive tutorials that teach HTML/CSS, JavaScript, JQuery, PHP, Python, Ruby, and more.
Coursera
Coursera is a free website that offers Massive Open Online Courses (MOOC) in many subjects with a lot of courses within Computer Science. Classes usually consist of video lectures, online quizzes, and homework assignments. Some courses offer certificates upon completion, and some even offer college credit if you sign up for the $50 paid credit course version.
Programming Practice
codewars
A free site that provides programming problems at varying difficulties. The better your code, the higher your rank becomes. These problems must be done in JavaScript.
Project Euler
A free site that provides tons of problems dealing with computer science and mathematics. You can solve them in whatever language you choose. It has over 400 problems, with one added every weekend.