Martin Luther King Jr. Day, a federal holiday designated as a national day of service to encourage all Americans to volunteer and improve their communities, according to the National Museum of African American History and Culture.

Martin Luther King Jr. Day is a federal holiday, but some shipping and delivery services may still be operational. Here's what we know.

The most transformational post-World War II president, Ronald Reagan, laid the foundation and put the wheels in motion to propel the country exactly to where we are today.

Democrats don't have a transformational leader to vanquish MAGA and risk being befuddled by President Trump's shock-and-awe campaign.

With all the attention, deservedly, on President Trump and what he intends to do with his defiant return to the White House, there’s a more than good chance we’ll spend the next four years consumed once again by all things Trump.

Former President Jimmy Carter’s recent death and funeral reminded Americans of his legacy and the values that motivated his public service.

The rug, which was in place during Ronald Reagan’s administration and during Trump’s first term, was reinstalled during Trump’s inauguration ceremony, according to CBS News. The Resolute Desk had to be partially disassembled in order to facilitate its return.

President Donald Trump found a letter from former President Biden in a drawer of the Resolute Desk in the Oval Office of the White House on Monday evening.

Although Martin Luther King Jr. Day is one of 13 federal holidays that is observed, inauguration day is not a federal holiday. Only employees who work in Washington D.C. observe the day by having the day off.

Ronald Reagan scribbled a note in 1989 to his successor above an elephant cartoon. The tradition, started perhaps inadvertently, was continued by Joe Biden.

MLK Day will be observed on Monday, Jan. 20 this year. U.S. Postal Service post offices will be closed on Monday, Jan. 20, and mail will not be delivered on the day, the USPS told USA TODAY. The USPS will resume regular operations on Tuesday, Jan. 21.

Monday is Martin Luther King Day. Here's what to know about the businesses and services that are closed for the holiday in Arizona.