A presidential memorandum (from Latin memorare, 'to remember') is a type of directive issued by the president of the United States to manage and govern the actions, practices, and policies of the various departments and agencies found under the executive branch of the United States government.
It has the force of law and is usually used to delegate tasks, direct specific government agencies to do something, or to start a regulatory process.
[1] Unlike executive orders, memoranda are not required by law to be published in the Federal Register, but publication is necessary in order to have "general applicability and legal effect".
[3] The Federal Register gives publication priority to executive orders and presidential proclamations over memoranda.
[2] A hortatory memorandum is issued as a broad policy statement, but unlike a presidential proclamation is directed to executive agencies.