Learn
82 free places to learn, sorted by what you want to do. None of them cost anything to start and none of these links earn me anything — they're simply where I'd send a friend.
Pick a goal
Every link was checked to open for a visitor who isn't signed in. A few — Skill Builder, Trailhead, Coursera — ask for a free account to track your progress, and Coursera and edX charge only for certificates. “Start here” marks where I'd begin.