Guitar is a versatile instrument that can produce bass, rhythm, lead, and percussion sounds with a single instrument. It attracts many people to learn due to its charm. There are 7 basic music notes (A, B, C, D, E, F, G) on the fretboard of a guitar, with additional sharp or flat notes between them. Memorizing the notes on a guitar's 6 strings and 20+ frets can be difficult, so it is easier to learn common guitar scales and memorize the notes within those scales. The document then provides examples of some common guitar scales, such as major and minor pentatonic, major and minor, harmonic minor, and major and minor blues scales.