I'm the guy who created freeCodeCamp. This article has some nice visualizations and insights, but gets one important thing wrong. Read it, but also read my response to it <a href="https://medium.com/@quincylarson/i-love-your-graphs-and-analysis-but-youve-got-one-thing-wrong-ba881b6a31db" rel="nofollow">https://medium.com/@quincylarson/i-love-your-graphs-and-anal...</a>