Diplomatic recognition is a political act by which one state acknowledges an act or status of another state or government, thereby according it legitimacy and expressing its intent to bring into force the domestic and international legal consequences of recognition. Recognition can be accorded either de facto or de jure, usually by a statement of the recognizing government.
Recognition of a government implies recognition of the state it governs, but not vice versa.
Another example is the United States non-recognition of the WWII annexation of the Baltic States by the Soviet Union. It continued to recognize the independence of these three states until surprisingly with the collapse of communism in the Soviet Union, these states once more came into being in fact, rather than just on paper.
Another example is the state of Israel in 1948, whose government was immediately recognized de facto by the United States.
(http://www.answers.com/topic/diplomatic-recognition)
Executive Agreements, a term signifying international agreements concluded by the president, as distinguished from treaties, which can be ratified by the president only with consent of the Senate. In international usage they are often called "treaties in simplified form," whether embodied in one text or in an exchange of notes.
the Rush-Bagot Agreement (1817) limiting armament on the Great Lakes; the exchange of notes enunciating the Open Door policy in China (1899, 1900); the Boxer Protocol (1901); the Gentlemen's Agreement (1907) on Japanese immigration; the Lansing-Ishii Agreement (1917) on Japanese interests in China; the armistices after the Revolution, the Spanish-American War, and the two world wars; the Atlantic Charter (1941); and the Moscow, Teheran, YALTA, and POTSDAM agreements during World War II (1943, 1945).
(http://www.answers.com/topic/executive-agreement)