Online Learning
Top-university open courses and skill platforms — many are free to audit.
Coursera与名校和大厂合作的系统性课程coursera.org
freeCodeCamp免费编程学习路径，含实战项目认证freecodecamp.org
Udemy技能课程市场，常年大幅折扣udemy.com
Anki间隔重复记忆卡片，背单词的终极方案apps.ankiweb.net
Open Culture汇总全网免费课程、电子书与电影openculture.com