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To help people understand CodePen who have never seen anything like it before, we made a one minute cartoon video to drive home the main points. It's not targeted at folks with zero knowledge about working on the web, it's targeted at our typical audience of web folks who land on CodePen who just aren't familiar with us.
We worked with the folks at ExplainMySite who make creating videos like this affordable for little businesses with even littler budgets.