本文根据这篇文章 12 New Companies That Will Make Going To College Unnecessary
是一个商业的网站，上面课程质量参差不齐，不过都是些实用课程，比如java，python，手机软件开发什么的。现在有免费的java入门课程，可以学习。Java for Complete Beginners
大部分免费，有的课程是需要教科书的。 A collaboration between MIT, Harvard, Berkeley, and other partner schools that let you take courses normally offered on-campus online. Students may choose to simply audit classes or they can complete assignments for a grade in order to receive a Certificate of Mastery. Subjects offered include law, history, science, engineering, business, social sciences, computer science, public health, and artificial intelligence.
Like edX, Coursera lets users take college courses from a wide range of schools around the United States. Topics of classes include humanities, medicine, biology, social sciences, mathematics, business, computer science, and more.
Like edX and Coursera, Udacity lets you take a variety of classes online for free in subjects that currently include computer science, cryptography, and physics. Udacity plans to let users get college credit for completing their courses. Interestingly, some courses are taught by famous instructors like Steve Huffman, one of the creators of Reddit.
A not-for-profit aimed at providing "a free world-class education for anyone anywhere." Subjects include physics, biology, chemistry, math, computer science, economics, history, and more. Classes are taught via instructional videos and interactive assessment tools.