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Now I Know

If you love learning about lots of random, interesting things, go sign up for Now I Know right now. Every day, Dan Lewis sends out an email about one really interesting topic.

Last week I learned that those white trails planes leave are called contrails, and they may actually help decrease global warming.

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🚀 I just relaunched my Vanilla JS Pocket Guides with new code examples and real projects to help tie everything you’ll learn together. Check it out.

Have any questions or comments about this post? Email me at or contact me on Twitter at @ChrisFerdinandi.

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