A tuba is a musical instrument that belongs to the brass family. It is the lowest-pitched instrument in the brass family and produces sound through lip vibration into a mouthpiece. The tuba first appeared in the mid-19th century, making it one of the newer instruments in the orchestra. A person who plays the tuba is called a tubaist, a tubist, or simply a tuba player. The tuba is used in a variety of musical settings, including orchestras, marching bands, drum and bugle corps, and jazz bands.

Some key facts about the tuba include:

• The tuba is generally constructed of brass, which is either unfinished, lacquered, or electro-plated with nickel, gold, or silver.
• Most modern military and brass band tubas are of two sizes used together: the E♭ bass (or bombardon) and the BB♭ bass, a fourth lower.
• The tuba family includes variations in structure and pitch, with the four main pitches being F, E♭, C, and B♭.
• The sousaphone, baritone, and euphonium are also companions of the tuba.

Overall, the tuba is an important instrument in the brass family, known for its deep, rich sound and versatility in various musical settings.