A tuning system is a system that is used to specify which of the infinite number of possible pitches can be used for composing and playing music.
The creation of a tuning system is complicated because musicians desire to make music with a large number of different pitches, but, as the number of allowable pitches is increased, conflicts (dissonance) arise regarding how they combine with each other. This complexity has led to the creation of a variety of different tuning systems, each with its own strengths and weaknesses.
The most common tuning system used in Western music is twelve-tone equal temperament, which divides the octave into twelve notes separated by logarithmically equal distances (100 cents). However, other tuning systems with twelve tones do not separate the tones with logarithmically equal distances, and still other systems divide the octave into other numbers of divisions, such as 19, 31 and 53.