Paper size a number of different sizes were defined for large sheets of paper, and paper sizes were defined by the sheet name and the number of times it had been folded. Thus a full sheet of "royal" paper was 25 × 20 inches, and "royal octavo" was this size folded three times, so as to make eight sheets, and was thus 10 × inches. Imperial sizes were used in the United Kingdom and its territories. These sizes are no longer commonly used since the UK switched to ISO sizes. Many of these sizes were only used for making books (see bookbinding),
Lead sheet while the rest of the group improvises an appropriate accompaniment based on the chord progression given in the chord symbols, followed by an improvised solo also based on the chord progression. Similarly, a sufficiently skilled jazz pianist should be able to accompany a singer and perform a song by her or himself using only a lead sheet. Lead sheets are also called fake sheets and collections of lead sheets are called "fakebooks". The melody, lyrics, and harmony define what a song is. In the music industry and entertainment law, a lead sheet is the document used to describe a song