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9 Reasons You Should Be Using CodePen
At CodePen.io, they describe themselves as a “playground for the front-end side of the web.” CodePen is great for testing out bugs, collaborating, and finding new inspiration. It works by allowing you to create “pens”, which are sets of HTML, CSS, and JavaScript. You can then display those pens on your profile, take feedback, and continue to edit those pens at any time.
Like many live code playgrounds, CodePen lets you learn in an open-source environment, displaying a live preview of the code changes, and even letting you embed your CodePen demos on any web page, like the one below.