edX

edX.org was founded by Harvard University and MIT in 2012, edX is a website that you can learn about a lot of subjects. There are courses about Computer Science, Data & Statistics, Business & Management, Language, Economics & Finance, Engineering, Humanities and Biology & Life Science from the world’s best universities and institutions.

Free and Online

All courses are totally free and online, you can start and end a course without spending a penny. But if you want a certificate you must pay between $49 and $99 (dolars).
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