Ways to get world-class education for free on the internet

As crucial as a university degree has become for working in the modern economy, it is not the only route forward into a wildly lucrative and satisfying career—just ask famous dropouts Bill Gates, Oprah Winfrey, Michael Dell, Steve Jobs, Mark Zuckerberg.

In the future, a single bachelor's degree in a particular subject will no longer suffice for many of us anyway. As robots and automation sweep the global workforce,hundreds of millions of people—the majority of whom do not have the time or money to go pick up a brand-new four-year degree—will have to "re-skill" in order to land new jobs. The question that employees and employers alike face is how to get that done quickly, efficiently, and, most importantly to many, cheaply.

The internet, luckily, is already a booming resource. Whether you find yourself seeking new employment mid-career, curious about alternatives to a college education, or simply are interested in learning for learning's sake, Quartz At Work has compiled some of the most dependable, high-quality materials you can access to learn anything on the internet.

For a free liberal arts education:

The first name in online course catalogs is Coursera, a juggernaut because of its pioneering of massive open online courses (MOOCs). Started in 2012, Coursera now has over 28 million users and over 2,000 courses—which can either be taken for free or for a small fee to earn an official certificate—from leading institutions like Harvard and Stanford.

In recent years, the catalog has expanded far beyond traditional subjects like history and mathematics. “There’s been a lot of interest in courses that are more about personal and professional development—you’ll see courses on how to learn, how to reason, how to find happiness and fulfillment, as well as courses that are more skills-oriented,” Coursera co-founder Daphne Koller told Quartz in 2016.

The platform's most popular classes include:

Machine Learning (Stanford University)Learning How to Learn (University of California-San Diego)Bitcoin and Cryptocurrency Technologies (Princeton University)Financial Markets (Yale University)Programming for Everybody(University of Michigan)Seeing Through Photographs (The Museum of Modern Art)Buddhism and Modern Psychology(Princeton University)Introduction to Philosophy (University of Edinburgh)

There are several other MOOC providers, including Udacity and edX. Udacity tends to be a better resource for professionals looking to develop certain vocational skills, and edX—created by MIT and Harvard—is more of a zany academic platform with a special focus on science, but both have large, comprehensive catalogs and easily searchable databases.

For specific professional skills, there's also Alison, another online course provider, which works with big publishers like Google and Macmillan to provide training in areas like customer service, project management, and human resources.

If your aim is purely to soak in all the knowledge under the sun, you might also give Khan Academy a try. The site is lauded for its streamlined, expert-driven content in the form of short YouTube videos that are quick to absorb and do not necessarily comprise an entire course.

And if you're interested in learning from professors at a specific institution, run a search for whether the school has an open learning program. Harvard Extension's Open Learning Initiative, Carnegie Mellon's Open Learning Initiative, MIT OpenCourseWare, and Open Yale Courses are all examples—and there are more coming out every year—of elite universities publicizing their most popular classes. (Quartz has a list of some of the newest.)

For learning a new language:

Many smartphone users are already familiar with Duolingo, which has emerged in recent years as a major language-learning program, beating out the likes of Rosetta Stone and other established companies for sheer efficiency. And, of course, cheapness.

Duolingo, which has about 200 million registered users around the world, currently offers 68 different language courses across 23 languages, with 22 more courses in development. It operates a "freemium" model (think Spotify) which allows users to access the bulk of the app for free, and pay for certain additional features. Its genius lies primarily in its design, which has been praised as revolutionary and intuitive: Lessons integrate text translation, visuals, speaking, and sound into a comprehensive learning environment.

For the euphoria of fiction:

Reading, the most wonderful of leisurely pursuits, need not be costly at all. Start at Project Gutenberg, which offers over 56,000 free e-books. Open Library, a project of Internet Archive that is trying to catalog every book in existence, also offers plenty of free books.

Join your local public library—or any public library—that offers OverDrive, an app that lets users borrow from a comprehensive catalog of free ebooks and audiobooks. Libby is another app that offers the same functionality with a better interface.

Google Books has abandoned its once-lofty plans to digitize the world's books, but it has a "free ebooks" feature you can toggle and is a useful site for academic texts or some more modern titles.

Quartz has a complete guide to finding specific titles online. (If you're a book novice, unsure of where to start, you might also take a look at Quartz's guide to enjoying classic literature.)

For the nitty-gritty of coding:

Coding is one of the best skills to learn online—the work itself takes place entirely on a computer—but the quality of free teaching available ranges from expert-level to deeply flawed. Programmers tend to agree, though, that Codecademy, Free Code Camp, and HackerRank are all consistently well-designed and useful resources.

Codecademy gently coaches novice coders through the basics of HTML and CSS, and into JavaScript and more complicated languages; Free Code Camp does the same with an added emphasis on building real-world projects for nonprofits. HackerRank offers code "challenges"—mini puzzles that are attention-engaging and educational without being explicitly instructive, providing a "learn by doing" approach that is ideal for people who prefer projects to lectures. If none of these three appeal, try this list of 49 vetted resources.

For a jumpstart on the hard-to-grasp:

Onerous is the idea of trying to learn more about the physical world without a good starting-off point. The following free resources, some of which live on a few of the open platforms mentioned above, offer a mix of interactive materials, quizzes, and videos, and are excellent inspiration for anyone interested in working in—or simply learning about—the sciences.

Greatest Unsolved Mysteries of the Universe (Australian National University) Understanding Einstein: The Special Theory of Relativity (Stanford University) Introduction to Astrophysics (École Polytechnique Fédérale de Lausanne) Quantum Mechanics for Everyone(Georgetown University)Math is Everywhere: Applications of Finite MathBBC Learning: ScienceMost Ambitious Science Projects (Highbrow)Super-Earths and Life (Harvard University)

For a hefty dose of motivation:

TED Talks are hardly a secret resource; you can easily find talks from stars in every industry from technology to agriculture. Another source of inspiration is MasterClass, which is not free—the current rate is $180/year—but hosts a number of well-made videos led by celebrities. Judd Apatow can teach you comedy, Gordon Ramsay offers wisdom on cooking, and Diane von Furstenberg will share her tips for building a fashion brand.

With these kinds of classes, the delivery platform is not as important so much as the idea of being inspired continually, by idols, icons, experts, or anyone that you feel can lead you to where you want to go, so that you maintain your energy and stay enthusiastic about the world around you.

MasterClass CEO David Rogier says, "Schools teach you the underlying skills of what to learn, but now in the changing world it's the default to change ourselves and continue to learn." Thanks to the internet, that's easier than ever.