Downpicking is a guitar-playing technique where you repeatedly hit the strings in a downward direction. It is also referred to as downstroke picking.
Rock and metal guitarists – such as Metallica’s James Hetfield – often prefer downpicking over alternate picking as it creates a heavier and more consistent sound.You can use downpicking to strike one or more strings, but it is thought to be a less efficient technique than alternate picking (playing both upstrokes and downstrokes).