TonalityGUIDE.com focuses on what is sometimes called common practice tonality - the characteristic tonal language employed in western music written some time after 1600 and mostly before 1910. Although tonal language changed across this time span and varied enormously within each period, the same basic principles underlie the organisation of pitch in most of the music of this era. TonalityGUIDE.com explores these principles and the different styles of music that they underpin.