Developers do not necessarily need a four-year degree to enter coding. Here are 20 tools to help you learn, exercise and polish your coding skills.
CodeAcademy is an online resource for the beginner programmer. With more than 45 million users, CodeAcademy is an extremely popular tool for learning a variety of programming languages, from HTML and CSS to Python and Ruby. Best of all, it's free. Click here to start.
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