U.S. President Barack Obama waves to supporters after delivering his farewell speech

President Barack Obama wrote a thank you letter to the American people on Thursday, expressing appreciation to the nation for the chance to serve.

"All that I've learned in my time in office, I've learned from you. You made me a better President, and you made me a better man," Obama wrote on his last day in office before President-elect Donald Trump's inauguration.

The president wrote about times when he witnessed technological and social progress and touched on major events such as the economic crisis.



He also asked Americans to devote themselves to building a better future, "not just when there's an election."

"And when the arc of progress seems slow, remember: America is not the project of any one person,'" the president wrote.

Read President Obama's full letter here.