GVIDO is the world's first digital sheet music score. The name GVIDO was given as a mark of respect to Guido d'Arezzo, who devised the foundations of musical notation in the early 11th century. Utilizing 13.1 inch wide dual electronic paper screens for crisp, detailed note reading. At only six millimeters thick and 660 grams in weight, the GVIDO provides excellent transportability and ease of use, with an excellent battery life that will last three days off just three hours of charge. Comments on your sheet music can be added or deleted with ease using the included stylus pen, and the extensive internal memory can store up to 4,000 scores.