The 10 Best Free Online Courses of 2016 According to Data

Online education has exploded in recent years, with millions of learners worldwide enrolling in massive open online courses (MOOCs) across various platforms. 2016 saw a diverse array of free online courses on everything from computer science to ancient philosophy to personal development. But which courses really stood out from the rest?

To determine the best free online courses of the year, we dug into the data. The rankings are based on an analysis of thousands of user reviews and ratings on Class Central, a discovery platform that aggregates courses from major providers like Coursera, edX, and Udacity. We also factored in enrollment numbers and completion rates to gauge the reach and effectiveness of each course.

After crunching the numbers, here are the top 10 free online courses of 2016:

1. Learning How to Learn: Powerful Mental Tools to Help You Master Tough Subjects

• Platform: Coursera
• University: University of California, San Diego
• Instructors: Dr. Barbara Oakley, Dr. Terrence Sejnowski

This blockbuster course claimed the #1 spot as the most popular MOOC of all time on Coursera, with over 1.8 million enrollments. Taught by an engineering professor and a neuroscientist, "Learning How to Learn" combines practical learning advice with insights from cognitive psychology and neuroscience research. Topics include overcoming procrastination, improving memory, and mastering difficult concepts.

Many reviewers praised the course for being engaging, informative, and applicable to learners of all ages and backgrounds. "This course is life-changing and so much more than the title implies," one reviewer wrote. "The knowledge and study tools gained will stay with you forever." By teaching learners how to learn more effectively, the instructors aim to provide a foundation for lifelong growth.

The course‘s stunning popularity points to the enduring demand for timeless meta-skills like learning how to learn. In an era of rapid technological change and professional disruption, the ability to pick up new knowledge and skills is becoming increasingly vital. Dr. Oakley and Dr. Sejnowski illuminate the science behind effective learning, empowering individuals to take control of their education.

2. An Introduction to Interactive Programming in Python

• Platform: Coursera
• University: Rice University
• Instructors: Joe Warren, Scott Rixner, John Greiner, Stephen Wong

This wildly popular computer science course, which forms part of a 7-course "Fundamentals of Computing" specialization on Coursera, eschews the traditional bottom-up approach to teaching programming. Rather than start with dry syntax and language constructs, the instructors immediately immerse learners in building simple interactive games like Pong and Blackjack using a browser-based Python programming environment.

*Learners build simple interactive games like Pong in the course‘s web-based Python programming environment. (Image source: Class Central)*

Many learners found this project-based approach highly engaging and non-intimidating for newcomers to coding. "This course took me from zero programming skills to building fun, interactive games in a matter of weeks," said one enthusiastic reviewer. "The instructors make the material accessible and the browser tool takes the hassle out of setting up your environment."

Over 500,000 learners have enrolled in the course and larger specialization, making it one of Coursera‘s most popular computer science offerings to date. The course‘s success reflects the growing interest in introductory programming education and the appeal of a hands-on, interactive approach to teaching coding.

3. Machine Learning

• Platform: Coursera
• University: Stanford University
• Instructor: Andrew Ng

Machine learning is a red-hot field powering everything from product recommendations to self-driving cars, and this Stanford course has become the definitive introduction for aspiring practitioners. Taught by celebrity AI researcher and Coursera co-founder Andrew Ng, the 11-week curriculum covers key supervised and unsupervised learning algorithms like linear regression, logistic regression, neural networks, and k-means clustering.

While learners should come in with some background in programming and basic linear algebra, Ng does an admirable job focusing on intuitive explanations and practical tips rather than dense mathematical proofs. Learners implement the algorithms in Octave, an accessible programming language for numerical computing, and complete quizzes and graded programming assignments to reinforce their understanding.

*Over 2.5 million learners have enrolled in Andrew Ng‘s highly regarded machine learning course. (Image source: Coursera)*

Many reviewers praised Ng for his knack for making a highly technical subject approachable and engaging for determined beginners. "Andrew is an incredible teacher and breaks down the math and intuition behind these powerful algorithms," said one learner. "It gave me the foundation I needed to start applying machine learning in my own projects and dive into more advanced topics."

The course has reached over 2.5 million enrollments, making it one of the most popular MOOCs ever. Its success reflects the central role of machine learning in the modern tech landscape and the widespread hunger for accessible yet rigorous training in a challenging and lucrative skill set. For both aspiring data scientists and non-technical professionals, Andrew Ng‘s course has earned its reputation as the gold standard introduction to machine learning.

4. Introduction to Computer Science

• Platform: edX
• University: Harvard University
• Instructors: David J. Malan

Harvard‘s CS50 has a reputation as the quintessential introductory computer science course, and the MOOC version on edX has reached an astronomical 2 million enrollments. Taught by dynamic instructor David Malan, the course provides a comprehensive freshman-level introduction to computer science and programming in C, Python, SQL, and JavaScript, as well as web development and basic algorithms.

The 12-week curriculum is structured around hands-on problem sets that challenge learners to apply their new coding skills to real-world projects like building a web scraper or a spell checker. Malan live-codes examples in lectures and provides extensive walkthrough videos to guide learners through the assignments. The course culminates in an open-ended final project where learners build a web app to solve a problem of their choosing.

*David Malan live-codes in front of a packed lecture hall in CS50, which has reached 2 million MOOC learners. (Image source: Harvard)*

While the course is demanding, Malan‘s energetic teaching style and the meticulously crafted learning experience won rave reviews. "CS50 is simply the best computer science course out there, period," gushed one reviewer. "Malan and his team have perfected the art of teaching computer science concepts in an engaging way and the problem sets are incredibly rewarding."

The runaway popularity of CS50 on edX speaks to the growing recognition of computer science as an essential foundation for the digital age. By providing an uncompromising yet accessible introduction to core programming and computer science concepts, the course equips learners to tackle tech‘s greatest challenges and unlock its most exciting opportunities. For aspiring software engineers and entrepreneurs, CS50 offers a world-class launchpad.

5. Programming for Everybody (Getting Started with Python)

• Platform: Coursera
• University: University of Michigan
• Instructor: Charles Severance (Dr. Chuck)

Python has skyrocketed in popularity as a versatile, beginner-friendly programming language, and this University of Michigan course offers an unintimidating entry point. Taught by the colorful Dr. Chuck (Charles Severance), the course covers fundamental programming concepts and basic Python syntax, accompanied by zany examples involving his pet Python, Lizzy.

Dr. Chuck‘s lighthearted yet lucid teaching style shines through the lecture videos, where he live-codes examples and visualizes core concepts with memorable analogies and illustrations. Each week, learners complete auto-graded quizzes and coding assignments to cement their understanding.

*Dr. Chuck brings a lighthearted touch to teaching Python fundamentals. (Image source: py4e.com)*

While the material stays at a beginner level, many reviewers found Dr. Chuck‘s explanations exceptionally clear and confidence-building. "This is an outstanding introduction to programming and Python from an instructor who clearly loves to teach," said one learner. "I came in with zero background in programming and now I feel comfortable reading and writing basic Python scripts."

The course has reached over 1 million enrollments and serves as the entrypoint to a 5-course "Python for Everybody" specialization on Coursera that extends into data structures, web scraping, and databases. Its popularity reflects Python‘s rapid rise as a lingua franca for domains from data science to web development. For aspiring programmers and data analysts, Dr. Chuck offers an encouraging initiation to coding in Python.

*The most popular courses on this list boast enrollments in the millions. (Image source: Class Central)*

Looking Ahead

Analyzing the list of 2016‘s most popular and highly rated online courses, a few trends emerge:

• Introductory programming and computer science courses continue to draw massive global demand. Four of the top five courses introduce programming and computer science fundamentals to beginners, reflecting the growing awareness of coding as a must-have skill for the 21st century.

• MOOCs are meeting the surging interest in applied data science and AI skills. Andrew Ng‘s machine learning course and other AI and data science offerings are educating millions of learners in powerful, highly compensated skill sets.

• Soft skills and digital literacy remain relevant alongside technical training. Several of the most popular courses teach widely applicable meta-skills like creative problem-solving, learning how to learn, and personal development. These evergreen topics may grow even more vital as technological change accelerates.

• Top courses increasingly blend video instruction with project-based learning and real-world applications. The highest-rated computer science courses immerse learners in hands-on projects like building games and web apps, fostering engagement and marketable portfolio pieces. Compelling production values and charismatic instructors also help courses stand out in an increasingly crowded marketplace.

• MOOCs are extending access to high-demand tech skills on a mind-boggling scale. The most popular courses now reach millions of learners, including many outside the traditional computer science pipeline. This has profound implications for the future of tech talent and diversity.

2016 was a milestone year for MOOCs and online education. As the top courses continue to reach new learners and improve their pedagogy, they are poised to play a central role in addressing the tech skills gap and shaping the future of work. For motivated learners around the globe, there has never been a more exciting time to build valuable tech skills through free online courses. We can‘t wait to see the new offerings and innovations that emerge in the years ahead.