The Cold War is generally considered to encompass the period from 1945 to 1991. The first date is that of the collapse of the alliance between the Allies in World War II and the collapse of the Soviet Union in 1991. The first use of the term "cold war" seems to have come from an essay by George Orwell in 1945 in the British newspaper The Tribune called "You and the Atomic Bomb". (The reference appears in the last sentence of the penultimate paragraph.)
Bernard Baruch, an advisor to President Truman, used the term in an address in April 1945, and later that year columnist Walter Lippman used the term and published a book with that title. Baruch's statement was: "Let us not be deceived. We are today in the midst of a cold war."
Through seven presidencies, and four and half decades, the world was gripped in a tense "non-shooting" war between the major states on the planet. The rivals, divided by economic and political systems, were in an ideological struggle that enveloped almost every continent. All through this period the shadow of atomic war loomed . The era was a time of spies and espionage that generated a whole genre of fiction and fear. American children were subjected to silly nuclear bomb drills that consisted of cringing under their wooden desks.
This was the era of the fallout shelter, the ICBM and intense distrust of our former allies. It also engendered proxy wars in foreign countries as both the East and the West tried to influence emerging governments in South America, Asia, Africa and Europe. Although the dismantling of the Berlin Wall may have precipitated the end of the Cold War, its effects linger in world diplomacy and that of the the United States.