A characteristic of all rondo forms is the regular reoccurrence of a(n) (instrumental) refrain.
The phenomenon rondo has a long history, starting in the medieval era with the French rondeau. In the course of history several schemes are developing:
The most simple one is: A-B-A-C-A-D,... also caled Italian rondo.
Lully introduced the rondo with two refrains: A-B-A-C-A, also called French rondo. This was a standard around 1750 in Europe. In the 17th and 18th century we see it spread across Europe. After that the rondo continues to evolve in late classical works, of which a specific example is the sonata-rondo or Viennese rondo form, with the scheme A-B-A-C-A-B-A, with often development-like techniques in the C-part. This last form can also be seen as a layered ternary form: Twice A-B-A separated by a central contrasting form section (C).
Also in the 19th and 20th century rondo forms continue to be used by composers (Schubert, Chopin, Schumann, R. Strauss, Bartók etc.).