Ektara (Bengali: একতারা, Punjabi: ਇਕ ਤਾਰਾ; literally “one-string”, also called iktar, ektar, yaktaro gopichand) is a one-string instrument most often used in traditional music from Bangladesh, India, Egypt, and Pakistan.
In origin the ektara was a regular string instrument of wandering bards and minstrels from India and is plucked with one finger. The ektara usually has a stretched single string, an animal skin over a head (made of dried pumpkin/gourd, wood or coconut) and pole neck or split bamboo cane neck.
Pressing the two halves of the neck together loosens the string, thus lowering its pitch. The modulation of the tone with each slight flexing of the neck gives the ektara its distinctive sound. There are no markings or measurements to indicate what pressure will produce what note, so the pressure is adjusted by ear.
The various sizes of ektara are soprano, tenor, and bass. The bass ektara, sometimes called a dotara often has two strings (as literally implied by do, “two”). Yet another version is khamak, one-headed drum with a string attached to it which is plucked. The only difference from ektara is that no bamboo is used to stretch the string,which is held by one hand, while being plucked by another.source-http://en.wikipedia.org/wiki/Ektara