Trump signed presidential memoranda, not executive orders: Here's the difference

President Trump signs a presidential memorandum to withdraw the U.S. from the 12-nation Trans-Pacific Partnership trade pact agreed to under the Obama administration on Jan. 23, 2017, in the Oval Office.

WASHINGTON — President Trump signed three high-level presidential directives on Monday, but they weren't executive orders.

Instead, they were styled as presidential memoranda, an increasingly common but lesser known expression of presidential power that came to replace many executive orders under President Obama.

Presidential memoranda are "executive orders by another name, and yet unique," wrote presidential scholar Phillip Cooper on his book

Both forms of presidential action have the force of law on the executive branch, and sometimes they seem to be used interchangeably. Even presidents sometimes mix them up, referring to memoranda as executive orders, as President Trump did Monday on Facebook.

"Something that's in a presidential memorandum in one administration might be captured in an executive order in another," Jim Hemphill of the Office of the Federal Register told USA TODAY in 2014. "There's no guidance that says, 'Mr. President, here's what needs to be in an executive order.'