A semitone, also called a half step or a half tone, is the smallest musical interval commonly used in Western tonal music, and it is considered the most dissonant when sounded harmonically. It is defined as the interval between two adjacent notes in a 12-tone scale (e.g. from C to C â¯).
The National Labor Union. The first large-scale U.S. union was the National Labor Union, founded in 1866 to organize skilled and unskilled laborers, farmers, and factory workers.
In 1955 the American Federation of Labor merged with the Congress of Industrial Organizations to create the AFL-CIO which has comprised the longest lasting and most influential labor federation in the United States and can still be found to this day.