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About TED-Ed Originals

TED-Ed Original lessons feature the words and ideas of educators brought to life by professional animators. Are you an educator or animator interested in creating a TED-Ed original? Nominate yourself here »

Meet The Creators

  • Educator Kim Preshoff
  • Script Editor Eleanor Nelsen
  • Sound Designer Stephen LaRosa
  • Narrator Julianna Zarzycki


Additional Resources for you to Explore
What is measured in parts per million, parts per billion, or parts per trillion? Take a look at some concentration analogies here. Commonly, substances thought of as contaminants or toxins such a PCB’s, lead, mercury, and pesticides, are measured in these small concentrations. Need a bit more about exactly what is meant by a ppm or ppb? This article will provide you with some more examples and explanations, as will what does ppm or ppb mean?

If you think parts per million is small, try imagining parts per billion. Parts per billion is a common measurement used for toxins in drinking water such as lead and mercury. Do you realize how minuscule of an amount that actually is? For lead, anything over 5 ppb is considered dangerous. That would be 5 parts of lead in a billion parts of water is cause for concern! This is how toxic Flint’s water really is gives some great visual examples and comparisons to take a look at, based on the water crisis in Flint, Michigan. There's been a lot of news about lead in drinking water and the potential harmful effects. But, how much lead is too much? Watch and scroll through this Washington Post infographic and find out more about Flint, Michigan. The Center for Disease Control is another place to find out valuable information regarding lead in drinking water applicable to anywhere in the world. 

Climate change is another topic where the term “parts per million” is discussed. This article: Atmospheric carbon dioxide levels are showing a startling increase is a great resource to learn more.

Have trouble understanding large numbers? Well, you are not alone. Humans have great difficulty conceptualizing large numbers. This video from the SciShow: Understanding the Most Extreme Numbers in the Universe suggests some ways to start to understand vast distances measured in the universe. 

Another way to increase your understanding is to scale things down. How to Develop A Better Sense of Scale—Better Explained, describes a very effective method of communicating large numbers in understandable language.

Ginormous Numbers Could Create a Mental Black Hole also gives some insight into the difficulty of large numbers to the human brain. How could the fact that we don’t really comprehend large numbers affect us? Read this article: Large numbers are dehumanising, so should big data worry us? to find out! Would a book help? Try Richard Evan Schwartz’s book: Really Big Numbers. Click here to watch a trailer about it.