Free online courses of 2019 — what excited the learners?

Nope, it is not machine learning, robotics, or data science at the top!

Shachee Swadia
4 min readOct 14, 2020

When I opened a weekly mail from freecodecamp, a link that caught my attention was about 100 most popular free online university courses offered for the first time ever in 2019. I love to take online courses, so I got all excited about this post and immediately opened the link.

The list is collated by Dhaval Shah and his team, of Class Central, a wonderful site that helps people in choosing which online course to take. Dhaval talks about Massive Open Online Courses or MOOCs and the method they used at Class Central to create the list.

The courses are free, the coffee and food are not! :)

What more can I do with this list?

Looking at the list, I got curious to know which courses and what categories were the most sought after. My guess for the leading categories was courses related to technology, seems right, yeah?

I realized that the best way to confirm my hunch would be to create a visualization. Class Central has an amazing catalogue which maintains information like the provider of the course, university offering it, category and sub-category, review rating and how many people bookmarked the course.

I decided to focus on the bookmark numbers to gauge the interest of the learners. I checked out the courses in the list and created the dataset for my visualization by noting down the name of the course, the category and sub-category the course was listed under, the course provider and the number of people who bookmarked that course.

Creating the visualization

My confidence about my guess for the top categories diminished as I collected the data. Since the courses had a category and sub-category, the hierarchy made me go for the tree map. Okay honestly, I love tree maps! :) So, I fired up Tableau Public Desktop and created a basic tree map from my dataset.

Well, well, well… For all the amazing benefits of data visualization, what I have come to value the most is that visualizations keep my premature presumptiveness in check! My guess was so far from the truth! Not one of the top 3 categories of courses started in 2019 that caught the attention of the learners was technology related!

Ah, what a powerful revelation the visual makes!

I tweaked my tree map with some visual formatting and colors that I think suited the category. Here is the tree map that shows which categories were hot for courses of 2019.

100 most popular free online courses that started in 2019

Treemap visualization created in Tableau
Treemap visualization created in Tableau

Insights from the tree map

The foremost insight is that the topmost category is Health and medicine. Maximum number of people are interested in learning about Multiple Sclerosis and ADHD - occurrence and awareness of both is on the rise globally in the recent times. Learners are also concerned with nutrition and wellness within the health category confirming the general trend of people becoming more health conscious.

Next two categories that piqued the learners’ interest are Social sciences and Personal development. Gender and sexuality along with human rights and psychology are the courses people are taking in Social sciences. This is a pleasant surprise that indicates people are being more open and sensitive to these concepts. Career development is the most sought-after course in Personal development.

Calculus in Mathematics, Agile in Software development and Civil engineering got the next level of interest from the learners. Business intelligence, Machine learning, Data analysis and Python are the courses that finally make it to the list. While these courses certainly have a lot of interest shown, I just expected them to be the forerunners. But they did not make the cut to the top 5 categories, which is in fact, refreshing.

Final words

Of course, there are so many existing courses for tech related categories but 2019 surely seemed to be the year where the learners were going beyond technology to widen their knowledge. A heightened interest in non-tech category of courses also indicates that the people taking up online courses are not just the techies.

Just to conclude I would like to put in a few words about free online courses and visualizations. MOOCs offer a great way to not only brush up our skills but also get information about issues affecting our normal lives. And visualizations have great potential to negate our assumptions and show us insights that cannot be garnered otherwise.


The team of Class Central created a list of the top 100 free online courses of 2019. My initial guess for the top categories was technology related courses. I created a tree map to confirm my assumption, but the visualization ended up proving me totally wrong! Health and medicine was the top category followed by Social sciences and Personal development. 2019 seemed to be the year of heightened interest in fields other than technology. This is great news as it indicates that people from tech and non-tech backgrounds are taking online courses to widen their knowledge about the general important topics.



Shachee Swadia

Visualizer. Writer. Coder. Hopeful humanist. Hopeless optimist. Happy soul.