The Demilitarized Zone
After a long period of negotiations, a new border was set up between North and South Korea, and it remains there even to this day. It runs roughly across the 38th Parallel, but is not straight at all. While it is called the Demilitarized Zone (DMZ), the thin strip of empty land (about 2 miles wide) that serves as a buffer zone between the two Koreans is in fact the most heavily militarized border in the world, with everything from landmines to loudspeakers stationed on both sides, with troops ready for war to break out once more.
The Forgotten War
The Korean War followed immediately after World War II, when the shock of a world war was still on everyone's mind. After the Korean War, several larger conflicts such as the Vietnam war drew the public attention away from the Korean War. In addition, the Korean War was relatively short, contained in a remote peninsula, and posed no threat to American civilians. It's no surprise that Korean War veterans sometimes refer to the conflict as the "Forgotten War" - it has, in fact, been somewhat forgotten.
Impact on the Cold War
The Korean War was the first armed conflict of the Cold War, and for many westerners, the beginning of the war against communism. As such, it increased tensions between the communists and the non-communists, and was really the thing that got the Cold War going.