The minor blues scale is a rich and expressive scale that adds depth and character to blues, rock, and jazz music. This scale is essentially a minor pentatonic scale with an additional note, known as the 'blue note', which adds a distinctive dissonance and emotional tension unique to the blues genre. The structure of the minor blues scale is: root (1), minor third (b3), perfect fourth (4), diminished fifth (also known as the flat five or b5), perfect fifth (5), and minor seventh (b7). This extra 'blue note' (b5) creates a raw and soulful sound, making it ideal for creating expressive solos and improvisations. Understanding how to incorporate these notes, particularly the flat five, into your guitar playing can dramatically enhance your phrasing and feel.