(CNN)It's just 35 words. But they make all the difference.
The oath of office that US presidents-elect have taken for 228 years marks the moment when citizens become historic figures -- leaders of the free world.
It's a promise that has endowed presidents with the power to change the lives of countless millions around the world.
But how much do you really know about the oath?
Test your knowledge with this quick quiz. See how you rate.
After you enjoy the quiz, get the entire story from CNN's newest mini-documentary, "The Oath: 35 words that make a President."
In this 11-minute special, narrator W. Kamau Bell takes a witty look back on this powerful tradition.
Through interviews with historians, reenactments, and even a trip to the Founding Fathers Pub, in Buffalo, New York, take an educational and entertaining journey to learn about one of America's greatest traditions.
'The End: Inside the Last Days of the Obama White House'
Also, for more about the inner workings of the presidency, CNN Films premieres "The End: Inside the Last Days of the Obama White House," premiering Wednesday at 9pm ET/PT on CNN.