Have you heard of coursera, Skillshare and edX? These are platforms, which offer free massive open online courses, so-called MOOCs. By taking these courses you can learn about topics such as Corporate Finance, Design Thinking or Facebook for Business and obtain official certificates upon completion of some classes. You will even find courses, which are given by professors of renowned universities like Stanford and Yale.
Check out this Lifehack article to get an overview of 25 different business courses offered.
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