1918 was a year in the 20th century.
- World War One ended on November 11, 1918. November 11 was celebrated as Armistice Day, and in 1954, became known as Veterans' Day. As such, Friday, November 11, 1955, was a day off for Hill Valley students.
- The Von Braun family, in Hill Valley for ten years, had changed its name to the more American sounding "Brown", a few years before Emmett Brown was born.
- Cannons from World War I were brought back after 1918 to the Hill Valley Courthouse lawn. They were moved sometime between 1955 and 1985.