Professionals are lining up to learn coding as a way to give their careers a new lease of life, with a slew of training companies cropping up to meet a booming interest in programming.

But many in the tech industry are warning that recruiting career-change techies is not enough, and that coding should be the C in a child's ABCs.

Coding - or computer programming - is a something of a buzzword at the moment, particularly among millennials looking to bag a well-paid first job. The explosion of sectors including big data, mobile apps and cyber security means there's plenty of roles out there - but many require developer skills.

Given this demand, it is little surprise that companies have sprung up to teach people how to code.

One such company is London-based Makers Academy. Its 12-week, full-time program - which costs ?8,000 ($13,585) - is designed for professionals looking for a change of career into a more technical role. Courses like this, which aim to train students to a level where they could get an entry-level development job, are known as coding boot camps.

"I was working as a developer myself and recruiters kept approaching me for jobs. It didn't take long for me to realize there was a great demand for skilled developers - but a lack of supply," Evgeny Shadchnev, co-founder and CEO of Makers Academy, told CNBC.

"We seized the opportunity. If your goal is to get a job as a software developer, we will get you there much faster than university."

And it's not just tech-savvy youngsters that are interested in developing, with Makers Academy's Shadchnev saying many of its students are frustrated professionals looking for a career change.

The U.S. Department of Labor expects the employment of software developers to grow 22 percent between 2012 and 2022, compared to an average growth across all occupations of 11 percent.

And according to the Graduate Management Admission Council's (GMAC) 2014 report, employers in both the U.S. and Europe rank technical and quantitative skills - which include coding - as the third most important selection criteria when it comes to recruitment.

In fact, some boot camps are so convinced their students will get good jobs that a number are betting their fees on it.

App Academy in San Francisco and New York, for instance, only charges its students after they get a job as a developer, after which it charges 18 percent of their starting salary. Seattle's Code Fellows, meanwhile, gives students a full refund (of the up-to-$5,000 fees) if they don't get a job within nine months of graduating.

Teach yourself

Not everyone is prepared to shell out thousands for coding courses, however. London-based Jules Coleman, co-founder of cleaner-booking website Hassle, taught herself.

"We wanted to start a company, but were from a much more corporate background, where making a PowerPoint presentation was as technical as it got," she told CNBC.

Coleman bought a hardback copy of Michael Hartl's tutorial on the web development framework "Ruby on Rails" from the local book shop, and built the company's first website.

"I taught myself over the weekends and in the evenings," she said. "I was very naive as to how difficult it would be, but you don't start by building Facebook - you start with baby steps."

Coleman stressed that to address the skills shortage that she encountered when Hassle first hired developers, coding bootcamps weren't enough.

"The next generation shouldn't be doing these bridging course - they need to be programming from the outset," she said.

Get 'em young

There is a growing drive to get children coding from an early age, and in England, coding will become a mandatory part of the school curriculum later this year.

In the U.S., meanwhile, Google launched Made with Code in June, and pledged a whopping $50 billion to inspire young girls to program in an effort to close the tech gender gap.

"If kids don't learn how to code there's a danger of a serious digital divide," warned Krishna Vedati, CEO of Tynker, a programming course aimed at children. "As the world evolves, if you don't know the basis of how the technology works, you'll get frustrated by it, and might get left behind."

Vedati developed Tynker after realizing his children were surrounded by technology, but didn't know how to make it. The result is an online or app-based coding course which is presented like a game for children.

That it's currently being used in over 10,000 schools across the U.S. demonstrates the push from both schools and parents for children to get up to speed when it comes to programming.

"We learned woodwork - our kids don't need to learn that. They're learning 3D printing instead," he said. "Programming isn't a fad. This is here to stay."


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