Staff

The staff is the fundamental latticework of music notation, upon which symbols are placed. The five stave lines and four intervening spaces correspond to pitches of the diatonic scale – which pitch is meant by a given line or space is defined by the clef.

Ledger or leger lines

Used to extend the staff to pitches that fall above or below it. Such ledger lines are placed behind the note heads, and extend a small distance to each side. Multiple ledger lines can be used when necessary to notate pitches even farther above or below the staff..

Bar line

Used to separate measures. Bar lines are extended to connect the upper and lower staffs of a grand staff.

Double bar line, Double barline

Used to separate two sections of music. Also used at changes in key signature, time signature or major changes in style or tempo.

Bold double bar line, Bold double barline

Used to indicate the conclusion of a movement or an entire composition.

Dotted bar line, Dotted barline

Subdivides long measures of complex meter into shorter segments for ease of reading, usually according to natural rhythmic subdivisions.

Accolade, brace

Connects two or more lines of music that are played simultaneously. Depending on the instruments playing, the brace, or accolade, will vary in designs and styles.