A tanda is a turn of dancing in a milonga

Milonga (place)

Milonga is a term for a place or an event where tango is danced. People who frequently go to milongas are sometimes called milongueros. The term "milonga" can also refer to a musical genre....

, and by association, a set of pieces of music, usually between three or five, that is played for one turn.

Most commonly the music is tango

Tango music

Tango is a style of ballroom dance music in 2/4 or 4/4 time that originated among European immigrant populations of Argentina and Uruguay . It is traditionally played by a sextet, known as the orquesta típica, which includes two violins, piano, double bass, and two bandoneons...

, milonga

Milonga

Milonga can refer to an Argentine, Uruguayan, and Southern Brazilian form of music which preceded the tango and the dance form which accompanies it, or to the term for places or events where the tango or Milonga are danced...

 or vals

Vals (music)

Vals is the Argentine tango music that features three-four time. The time between two successive beats in the Vals is divided into three sub-sections of equal duration. In contrast to the Vals, in the tango and the milonga, there are two sub-divisions...

. Often between tandas is played a cortina

Cortina (tango)

A cortina is a short piece of non-dance music that is played between tandas at a milonga . The cortina lets the dancers know that the tanda has ended. The partners can then without insult thank each other and return to their own tables, to find a new dance partner at the next tanda...

 (Spanish for "curtains"), a musical pause to allow dancers to leave the floor and to serve as a short break between tandas.

Tandas are normally arranged by feel of the music. A typical order of tandas is: T-T-V-T-T-M or T-T-V-T-M (T for a tanda of tangos, V for a tanda of vals cruzado, M for a tanda of milongas). Usually the last tango song of the last tanda is "La cumparsita".

Sometimes in a minority of milongas in Argentina also non-tango tandas are played, like Rock n roll

Rock N Roll

-Personnel:*Ryan Adams - Bass, Composer, Costume Design, Guitar, Keyboards, Multi Instruments, Vocals, Vocals *Billie Joe Armstrong - Vocals *Melissa Auf der Maur - Vocals...

, Cumbia

Cumbia

Cumbia is a music genre popular across Latin America. The cumbia originated in the Caribbean coast of Colombia, where it is associated with an eponymous dance and has since spread as far as Mexico and Argentina...

 or Chacarera

Chacarera

The Chacarera is a dance of Argentine origin. It is a genre of folk music that, for many Argentines, serves as a rural counterpart to the cosmopolitan imagery of the Tango...

, but not more than 1 tanda.