First is
the front line (the comissão de frente), which consists of around ten
people who have to introduce the samba school's theme. Other than that, there
is no rule concerning the order of the different elements of a samba school. Its
main components are:

• The master of ceremonies and flag bearer:
  a couple, sometimes dressed in royal eighteenth or nineteenth-century
  attire, who dance in a graceful, composed manner. The flag bearer displays
  the flag of the samba school. The rich costumes that the couple wear are a
  mark of the intense dialogues between cultures provided by the Carnival in
  Rio.
• The Baianas (ala de baianas), which
  may include over one hundred older Afro-Brazilian women stereotypically
  dressed to represent the women from Bahia who sold goods in the streets of Rio during the 19th century.
• The drum section (bateria) which
  consists of a few hundred men playing in rows. Instruments include
  a variety of drums, tambourines, and rattles.
• The opulent floats.