And part formatting. I’ve seen many different ways of notating music, from lyric sheets with chord names over the lyrics to publisher quality typesetting. It varies depending on the setting, usually, (but not always!) with the lyric/chord sheets coming from singer-songwriters and the fully notated charts done by an arranger/orchestrator for a large scale studio session or concert performance. Lyric/chord sheets are cool, and they can actually work better if the desired outcome is to play freely and creatively without getting bogged down in reading.