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Wistia video thumbnail - Jam Handy - Differential Gear

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Originally titled "Around the Corner", this video is in the Public Domain and can be used by anyone. You can find and download the original video here. Find all Jam Handy videos here.

One of the engineering feats that changed cars in the 1930s was the introduction of the differential gear and the Jam Handy Organization set out to explain it to the car-buying public. This was a serious explanation challenge due a number of factors.

  • People were not well-informed about the mechanics of cars
  • The gear is complicated and little information existed that was oriented toward non-engineers
  • Gears, like most car parts, are hidden and can seem boring.

The manner in which Mr. Handy went about solving these problems is a classic model in explanation.

Did you notice how much time passed before the differential gear was introduced? About 90% of the video passed before it was mentioned. Yet, it's undeniably powerful.

Here are a few things that make it powerful:

  • It answers a different kind of question. Instead of “what is a differential gear?” it asks “why does it make sense that this gear exists?”
  • The language of the video is aimed at the car-buying public. It’s not for engineers.
  • It builds context so that the gear is part of a bigger picture that every viewer can see.

This is context in action. As explainers, building context effectively is one of the most useful skills we can develop.

Are you ready to learn the secrets of explanation excellence? Check out the Explanation Master Course.