Mechanical pencil applied at an angle. When excess vertical pressure is applied on the lead, the lead is automatically retracted inwards. Higher-end mechanical pencils often feature a lead hardness grade indicator and sometimes feature a retractable lead guide pipe. This allows the lead guide pipe to retract back into the pencil body, which will keep it protected in storage and during transit and makes it 'pocket-safe'. In spite of the name, pencil leads do not contain the toxic chemical element lead, but are typically made with graphite and clay, or plastic polymers. Compared to standard pencils, mechanical pencils have a smaller range
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