Editing Binary form (section)

===Symmetrical vs. asymmetrical===
If the ''A'' and ''B'' sections are roughly equal in length, the design is referred to as '''symmetrical'''.

If the ''A'' and ''B'' sections are of unequal length, the design is referred to as '''asymmetrical'''. In such cases, the ''B'' section is usually longer than the ''A'' section.

The asymmetrical binary form becomes more common than the symmetrical type from about the time of Beethoven, and is almost routine in the main sections of Minuet and Trio or Scherzo and Trio movements in works from this period. In such cases, occasionally only the first section of the binary structure is marked to be repeated.

Although most of [[Chopin nocturnes|Chopin's nocturne]]s are in an overall [[ternary form]], quite often the individual sections (either the A, the B, or both) are in binary form, most often of the asymmetrical variety. If a section of this binary structure is repeated, in this case it is written out again in full, usually considerably varied, rather than enclosed between repeat signs.