Octave and pitch pedals alter pitch by shifting notes up or down, often used for bass emulation, harmony layering, or extreme effects. Early analog octave pedals like the Boss OC-2 introduced monophonic tracking, while modern digital units provide polyphonic and glitch-free shifting. Notable models include the Electro-Harmonix POG series, Eventide PitchFactor, Digitech Whammy, and Boss OC-5. These pedals are useful in rock, funk, and experimental music, allowing guitarists to simulate bass lines, create synth-like textures, or add harmonized leads. They work well with fuzz and modulation effects for unique sonic landscapes.