The tambura is a type of a stringed stringed instrument. It is a long-necked Indian lute, which is unfretted and round-bodied. The neck is hollow, and it has four or five wire strings, which are plucked one after another in a regular pattern to create a tonic resonance field. In the Hindustani classical music, the tambura comes in different sizes: bigger "males" and smaller "females". The male instrument has an open string length of one metre, the female is sized down to 3/4. The Tambura is designed in three different styles:

Miraj Style: The favourite form for Hindustani performers, it is usually between three to five feet in length, with a well-rounded resonator plate (tabali) and a long, hollow straight neck. The round lower chamber to which the tabli and the neck (dandh) are fixed is actually a selected and dried gourd (tumba).
Tanjore Style: A south Indian style of tambura, used widely by Carnatic music performers. It has a different shape and style of decoration, but is otherwise much the same size as the Miraj style. Typically, no gourd is used, but the spherical part is gouged out of a solid block of wood. The neck is somewhat smaller in diameter.
Tamburi Style: This style is much more popular recently, due to its small size and portability. It is two to three feet long, with a shallow resonator and a slightly curved tabali. It may have from four to six strings. The small five-string tamburi are tuned to the higher octave and are the preferred instruments for providing the drone for solo-performances by string-playing artists.