The acoustic bass, also known as the double bass or upright bass, is a large string instrument that produces deep, resonant sounds. It typically has four strings, tuned in perfect fourths, and is played with a bow or by plucking the strings with the fingers. The body of the instrument is hollow, allowing it to amplify the sound naturally. This instrument is commonly used in various music genres, including classical, jazz, and folk. The acoustic bass provides the harmonic foundation in ensembles and orchestras, complementing other instruments like the cello and piano. Its rich tone and versatility make it a vital part of many musical traditions.