Most programmers are partly self-taught—and anyone looking to get involved in the industry better follow suit. So says a new survey of 39,000 software developers published by HackerRank.

All by myself: About 74 percent of software developers are at least partially self-taught. That’s essential in an industry that’s introducing new languages, frameworks, or tools on a frequent basis—the knowledge gained from a college degree lasts only so long.

Start early: The study found that 25 percent of developers learned to code before they could learn to drive. The UK had the highest share of early birds—about 11 percent of coders polled there started between the age of five and 10.

Where to learn: Interested? Most coders say they turn to the developer community Stack Overflow, as well as YouTube, to develop skills. Only 60 percent use good old-fashioned books to learn.

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