Slide guitar is a technique used in playing the guitar where a smooth object, often called a slide, is placed on the strings. This allows the player to create a gliding sound between notes, producing a unique and expressive tone. The slide can be made from various materials, such as glass, metal, or ceramic, and is typically worn on a finger. This style is commonly associated with genres like blues, country, and rock. Notable musicians, such as Duane Allman and Robert Johnson, have popularized slide guitar, showcasing its emotional depth and versatility. The technique can be played on both electric and acoustic guitars.