What are TED Talks?

TED Talks are short, informative presentations created by people from all walks of life.

In the past decade, they've become an incredible force for promoting social change and the spread of new ideas.

What makes them so influential?

What makes a TED Talk worth watching?

The History of TED

Here are the two men that started it all: Richard Saul Wurman and Harry Marks.

In the early 80s, they found themselves inspired by the convergence of technology, entertainment, and design.

This led them to hold the first TED Conference in 1984. Industry professionals from these three fields came together and gave presentations about their discoveries.

In 1990, the TED Conference became an annual event, and it expanded to include speakers from more fields. Here are some of the talks from this time that are available to watch on the TED website.

The TED conferences from this decade inspired many people, but financially, they were only a modest success.

This changed in the 2000s. When Richard Saul Wurman retired, he passed the TED Organization over to Chris Anderson, a businessman and TED enthusiast.

Under Anderson's leadership, the TED Organization expanded its operations. It became a non-profit, and it opened up conference tickets to the public. Anderson worked to curate more talks and speakers.

Then, in 2006, the TED organization decided to release recorded TED Talks on the web, free to view.

Within just a few months, these videos gained 1 million views.

The introduction of TEDx offered a way to contribute to the TED project outside of the formal conference setting. Between this and other expansion efforts, the number of TED Talks being released online skyrocketed.

Here are all the videos that have been posted on TED's website up to 2017.

The TED Formula

How else can we try to understand the TED phenomenon? Obviously, their videos are free to watch online, but there must be more to them that would explain their astonishing popularity.

What else is special about these talks that make them worth watching?

Talk Length

Talks generally have a time limit of 18 minutes. They want ideas to be as concise as possible, so the most viewed videos are often the shortest ones.


Beyond simply being concise, TED talks are expected to be easily understood by the general population. After all, talks are meant for the whole world to listen to.

Using the available audio transcripts for each talk on the TED website, we performed a Flesch-Kincaid readability analysis to quantify just how understandable they are. We find that, on average, TED talks are presented at about a seventh-grade reading level.

TED talks historically centered on the combination of Technology, Entertainment, and Design. With the expansion of the TED organization over years, the variety of talk themes also evolved. The content was no longer tied to the thematic interests of the founders, but grew to reflect the impactful work of citizens across the world.

We notice that the original themes have prominent rankings during earlier years. We see a spike in Entertainment content in 2008, before finally falling from the top chart after 2011.

Try clicking on the Entertainment item in the figure legend (Click again to return to the full figure)

The theme of Design trends downward, before also dropping from the list after 2015.

The theme of technology appears consistently at the top of the chart, indicating the enduring interest and relevancy of technology. Though, while technology does not slip from the board, we do observe a drop in the most recent years.

Most recently, we observe a thematic shift towards humanism. Society, humanity, social change, and communication all appear on the top five list in 2017. All of these are new to the top five themes as of 2016 or later.

Do any of your interests make the top five?

Understanding Popularity

The previous visualization addresses the question of theme popularity from the presenters’ perspective. We next wanted to understand popularity from the perspective of the viewer.

The publication of these videos to the internet made them accessible to billions of potential viewers. Through the TED service, these viewers had the ability to comment and submit reactions to presentations they watched.

From these data, we developed a set of four popularity metrics to understand which talk themes were most popular:

  3. Engagement
  4. Positivity

The comments metric measures the number of comments submitted for videos of a particular theme.

Submitting a comment requires the commenter to first create a site account. This additional step might dissuade the casual viewer from entering into the dialogue. We therefore expect this measure to assess popularity amongst more invested viewers.

We notice that many of these tags are polarizing in nature. Religious themes are found throughout this top ten list, with atheism and God occupying the top two positions. Atheism particularly dominates the view, with more than twice the number of comments as any other topic.

The views metric represents the average number of views across all videos within a theme category. This represents a raw measure of the reach of the content. The view-counts here are in the millions, indicating the magnitude of this reach.

We notice that videos related to body language were the most viewed of all content. This may indicate an interest in viewers to learn about this aspect of public speaking for their own presentations.

Engagement represents the ratio of comments to views. While this metric is then highly correlated with the comment metric, it allows the comparison of commenting behavior without penalization for lower view count.

As in the case of the comment comparison, we observe that atheism is at the top of the list. However, the gap between this top category and others is much smaller than before. Again, we notice that polarizing topics are represented here.

The positivity metric represents the ratio between positive and negative reactions. This metric then represents the degree to which audiences viewed presentations in a positive light.

Addiction is at the top of the list and dominates this metric, with more than double the positivity value of the next highest talk theme.

We notice a trend for the focus on disadvantaged or disenfranchised communities. This positivity would then signal support from the TED viewing audience.

Now it's your turn!

We've created a tool that let's you explore all the TED talks in our database by their ratings.

Simply click on any rating to sort talks by that rating. Using the selectors on the bottom left, you can search for specific talks, speakers, or speaker professions. Select "All" in any selector to view return to the original view.

Whenever the title is displaying the name of a talk, you can click the title to go straight to the TED website and view the talk for yourself!