Blu is a musical instrument for children. Drawing inspiration from a musical keyboard, it reinvents the idea of keys and presents itself as a highly modular, versatile product. By positioning the movable keys, the user can determine the note and the instant in time in which they are to be played. Blu provides an experience analogous to that of playing with building blocks; by playing with the keys, the child understands advanced concepts and acquires a good sense of timing and improvisation.