Memorial Day, an American holiday observed on the last Monday of May, honors men and women who died while serving in the U.S. military.

"It's a day we remember those who never made it home; those who never had the chance to take off the uniform and be honored as a veteran," U.S. President Barack Obama said Saturday in his weekly address.

Obama said the idea for Memorial Day came from "ordinary citizens who acknowledged that while we can't build monuments to every heroic act of every warrior we lost in battle, we can keep their memories alive by taking one day out of the year to decorate the places where they're buried."

He said he has "no more solemn obligation than leading our men and women in uniform. ... Making sure we only send them into harm's way when it's absolutely necessary."

Obama said he and first lady Michelle Obama "have spent quiet moments with the families of the fallen. ... They've shared their pain, but also their pride in the sacrifices their loved ones made under our proud  flag."

He also urged Americans on this Memorial Day weekend to "take a moment and offer a silent word of prayer or public word of thanks" to the country's veterans.

The president also suggested laying flowers "at a fallen hero's final resting place" or sending "a care package to our troops overseas" or hiring a veteran "who is ready and willing to serve at home just as they did abroad."

"The debt we owe our fallen heroes is one we can never truly repay," Obama said.

WATCH: President Obama's Memorial Day address